We’ve already observed how GM was unique among the Big 3 US automakers in having bespoke V8 engines for each of its five automobile divisions. Contrast this with Ford Motor Company and Chrysler Corporation, both of which were sharing V8 engine architectures among their various brands since the 1950s.
Today, division-specific powertrains at GM are a distant memory, and all engines are now simply “GM” engines. So when (and how) exactly did this transformation take place? Note that I’ll be limiting my discussion to V8 engines in this post: Six and four-cylinder engines (which were shared much more freely at GM) will be the topic of a future post.
Even for a company as big as GM, it is expensive to have distinct small- and big-block V8 engine families for each division. It didn’t take the bean counters at GM long to realize that this was not a sustainable situation, especially once GM’s market share began its long slide from its peak of 50% in 1962. Cracks appeared in the facade starting in the 1960s as GM divisions began to swap V8 engines, with the practice entering public consciousness in 1977 with the breaking of the Oldsmobile-Chevrolet engine scandal.
GM learned their lesson after the 1977 scandal, and the lesson was the correct one: The issue wasn’t so much that engine swapping was bad (after all, Ford and Chrysler were already doing it). Rather, the problem was the failure to properly disclose the engine sharing and, and more broadly, the continued use of divisional specific engines and divisional engine branding. After 1977, GM engine swapping rapidly picked up speed, so it wouldn’t be long before some divisions stopped making their own V8 engines altogether and made the switch over to “corporate” powertrains.
When I first hatched the idea for this article, I was surprised to find that I couldn’t answer the question posed by the title, and I’m guessing that many of our readers can’t either. But perhaps I shouldn’t have been so surprised: GM didn’t make a lot of noise at the time about the “last Buick engine” or “last Pontiac engine,” and for a good reason: Aside from the 1977 scandal (which was largely manufactured by lawyers and amplified by the media), buyers typically didn’t care. As a result, all of GM’s division-specific V8 engines snuck out in the middle of the night with a nary whimper.
Buick
1961 Buick 215 V8
Buick was actually the first GM division to share its V8 engines with other brands, going all the way back to their all-aluminum 215 cu. in. V8, which first appeared in the 1961 Buick Special (a full 16 years before the 1977 engine scandal). This engine would be used in the 1961-62 Pontiac Tempest and in the 1961-63 Oldsmobile F-85 (the latter application employing a modified head and angled valve covers to make it look more like other Oldsmobile engines). The Oldsmobile version of this engine would also gain a turbocharger in 1962. This initial experiment in V8 engine sharing would be short-lived, however. By 1964, each division was using their own V8 engines in their senior compacts. Almost a decade would pass before any GM division would share a V8 engine again.
1975 Buick Skylark
Buick first started using V8 engines from other divisions with the 1975 Skylark, which used the Oldsmobile 260 V8 for its smallest V8 engine option. The 305 Chevrolet small-block V8 was also available in the Skylark starting that same year.
By 1977, the engine sharing floodgates were wide open at GM, and the Oldsmobile 403 V8 began to show up in the Buick LeSabre, Electra, Riviera, and Estate Wagon. The Chevrolet 305 would show up in the Regal in the following year.
While Buick may have been a judicious engine borrower, they were a stingy lender: Their V8 engines rarely appeared in non-Buick branded cars. Because of this limited reusability, Buick, the first division to share its V8 engine, would become the first GM brand to stop making its own V8 engines in 1980. The last Buicks powered by Buick V8 engines were the 1980 LeSabre, Electra, and Estate Wagon. After that, all V8 engines sold by Buick were sourced from other divisions.
As an interesting footnote, GM sold the tooling and design of the aluminum 215 V8 to Rover in 1967. Variations of this engine would remain in production (as a Rover V8) until 2003, outliving its successor Buick V8 engines by several decades.
Pontiac
Pontiac was not as promiscuous with their engines as some of the other GM divisions, with most of their V8 engines being used in their own cars, which put them in a similar position to Buick by the late 1970s.
1971 Pontiac Ventura
That said, Pontiac holds the second-earliest example of V8 engine sharing at GM that I could find (after the 1961 Buick 215 V8): Specifically, Pontiac was using a Chevrolet 307 V8 as the optional V8 engine in the 1971 Ventura. Indeed, at varying times over the course of its six-year run, the Ventura would be sold with V8 engines made by Chevrolet, Oldsmobile, Buick, and Pontiac, making the Ventura one of GM’s biggest ever engine transplant recipients.
The new for 1977 Pontiac 301 cu. in. V8 was used in various Buicks from 1977 until 1981. The peculiar Pontiac 4.3 liter 265 V8, a de-bored version of the 301, appeared for only two model years, 1980 and 1981. In addition to Pontiac vehicles, this engine was available in the Buick Regal, Buick Century, and Oldsmobile 88.
One year after Buick ceased making their V8 engines, Pontiac would be the next GM division to completely stop making its own V8 engines. The last Pontiac V8 engines were built in the 1981 model year – thereafter, Pontiac used GM V8 engines sourced from other divisions in their cars.
Oldsmobile
As I mentioned at the beginning of this article, Oldsmobile famously started using Chevrolet 350 V8 engines in the Delta 88 in 1977. Still, Oldsmobile on the whole was more of an engine donor than a borrower, with their 350 and 403 V8 engines picking up the slack over at Buick and Pontiac after those divisions stopped making their own V8 engines in 1980 and 1981, respectively.
Oldsmobile was also the sole maker of passenger diesel engines for all of GM in the 1970s and 1980s, which were used by all five automotive divisions. Actually, GMC used the Oldsmobile 350 diesel V8 in the Caballero from 1980 to 1984, possibly making this (along with the SBC) the only engine to ever be used across all six traditional GM divisions.
Oldsmobile would stop making the 403 in 1979, and the gas-powered version of the 350 V8 in 1981, although the diesel would stay in production until 1985. A smaller 307 cu. in. V8 would stay in production until 1990, and would eventually be used by every GM car division (excluding Saturn). 1990 would mark the end of Oldsmobile produced V8 engines at GM.
The Aurora would debut in 1995 with a DOHC V8 engine, but this was a derivative of the Cadillac Northstar engine and not an Oldsmobile design.
Cadillac
Cadillac was the only GM division to never share its OHV V8 engines with any other division (although the modern DOHC 32-valve Northstar engine would eventually be shared with Oldsmobile, Buick, and even Pontiac).
Cadillac began borrowing V8 engines from other GM divisions in 1976 when the Seville launched with an Oldsmobile 350 V8 as its sole engine. Granted, the 350 in the Seville was fuel-injected, while all other applications of the Olds 350 that year were still carbureted.
Starting in 1986, Cadillac began using a variety of Oldsmobile and Chevrolet V8 engines in their cars to supplement the trouble-prone Cadillac-exclusive HT-4100 V8 engine. Variations of the Cadillac High Technology (HT) engine would continue to be used in Cadillacs up until 1995, as the Northstar V8 gradually started replacing it beginning in 1991.
As previously, mentioned, the Northstar V8 would be the first Cadillac engine to be shared with other GM divisions. It would go out of production in 2011. You might think this would be the end of the line for Cadillac-branded V8 engines, but there was one more.
2019 Cadillac Blackwing V8 Engine
Cadillac’s last exclusive engine was the 4.2 liter Twin-Turbo “Blackwing” engine, used for only one model year in the 2019 CT6-V. With an estimated unit cost of $20,000, this is easily one of GM’s most expensive (and short-lived) engine flops. Note that newer (post-2020) Cadillac Blackwing engines have no relationship to this engine: The CT-5 Blackwing uses a supercharged 6.2L GM V8, while the CT-4 Blackwing uses a twin-turbo V6.
So Cadillac earns the honor of being the last GM division to produce its own V8 engines, and quite recently too.
Chevrolet
Chevrolet is the Type O-Negative (universal donor) of GM, its V8 engines having been used by every car and truck division. Detailing all the Chevrolet engine sharing would take more space than I have here, so I’ll just cover the highlights here.
1993 Cadillac Fleetwood – powered by Chevrolet
As previously mentioned, the 1971 Pontiac Ventura was the first non-Chevrolet car to receive a Chevy engine. By the mid 70’s Chevrolet V8 engines were regularly appearing in Pontiacs, Oldsmobiles, and Buicks, and could even be found under the hoods of Cadillac cars and trucks starting in 1990.
While Chevrolet may have been a prodigious donor, other divisions’ V8 engines almost never appeared in Chevrolet-branded cars, with the Oldsmobile diesel being the only exception I could find.
The Chevrolet small-block V8 would go through several iterations of refinement over the decades, gradually losing its Chevrolet branding to become a GM V8 engine (ultimately in Generation I and Generation II guise). The automobile-only Gen II would last appear in the 1997 Camaro and Firebird, while the predecessor Gen I would continue to be used in various truck applications until 2005. The successor GM LS small-block V8 engine, introduced in 1997, was a clean-sheet design and shared only bore spacing with the predecessor SBC.
Bonus: GMC
GMC 637 V8
Starting in 1955 when it first started offering V8 engines, GMC relied on eight-cylinder engines from Pontiac, Chevrolet, and Oldsmobile, making this truly the earliest example of V8 engine sharing at GM, albeit in trucks and not cars. I guess GM figured truck buyers didn’t care as much as car buyers where their engines came from.
For most of its existence, GMC did not have its own gasoline V8 engine, save for a brief time from 1967 to 1972 when GMC sold an eight-cylinder version of their 60-degree V6/V12 engine. This massive, 637 cu. in. (10.4 liter) V8 engine weighed over 1,200 pounds. Alas, this bruiser was never fitted to any light-duty C/K series pickups – it was only available in larger commercial chassis and COE configurations. This is too bad because it could have been the Ram SRT-10 of its day.
Tom, I commend you for such an interesting article.
I have one point I wanted to make, and that was with Oldsmobile/Cadillac.
It is commonly pointed out that the Northstar V8 is a Cadillac motor. However, from what I have been able to find, the Northstar actually shares nothing with Cadillac and bears relations to a completely different engine, that engine being the… Oldsmobile Quad 4.
When I had a Facebook account back in the day, I did some research on this as I had heard that Oldsmobile, not Cadillac was the one who did R&D on the Northstar starting in 1984. Only late in the engines development did it switch over to being a Cadillac engine, when Cadillac discovered that their HT series was not going to be adequate for the direction they wanted to go in the 90s. If you do some digging (and if anyone is interested, I still have all of this saved somewhere) there is a prototype engine called the Quad 8 that bears a striking resemblance to the Northstar. Internal designs are not the same between the Northstar and Quad, but they are eerily similar, leading me to believe that whoever worked on the Quad, worked on the Northstar. Which would be Olds
There is a book out there that supposedly covers the Northstar. Don’t bother reading it. I did and it’s terrible. It tries to make a correlation between the Northstar and the Corvette LT5, which is simply not possible.
If anyone would like me to dig this stuff up, or heck, even put in an article, I’d be happy to do so.
Now that you mentioned it, I seem to recall reading something about a “Quad Eight” back in the day.
Thanks.
“the Northstar V8 gradually started replacing it beginning in 1991.”
Wasn’t that 1993 in the Allante, STS, and Eldorado TC?
The ridiculously short life of the Blackwing V8 is one reason I hate EVs. I was hoping they’d make a NA version to replace the 3.6 V6 in other Cadillacs.
The Buick small iron V8 is the most interesting to me, as it was tied to the early 215 aluminum V8, which led to unusually small bore centers and a long stroke to get to the 350 cubic inches that seemed to be the requirement by the late 60s. It should have been the easiest to scale back down, but then they were probably constrained in production more than any of the others.
I have always suspected that the biggest driver of consolidation was the beginnings of the emissions era, followed by the beginnings of the CAFE era. Both of those situations required a lot of expensive engineering and certification, making Divisional overlap much more expensive than in the pre-regulation era.
Without knowing for sure, I would guess that none of the big block/big displacement engines were shared? None are coming to mind.
I’ve read (somewhere, not recently) that Oldsmobile was favored as a divisional engine because it was easier to “clean up” for emissions than the Pontiac and Buick engines. The Chevy’s ubiquity made it the other obvious choice; aside from that, it’s obviously a good engine – it lasted 50 years, and much longer if you count the aftermarket.
Great article Tom – this period of GM development has always fascinated me. Pontiac people especially often feel that no real Pontiac was built after 1981. 🙂 Buick people don’t seem quite as fanatical, probably thanks to the Grand National.
…and to V6 engines being the center of development at Buick since the mid-’70s, with the original odd-firing 231 evolving into the awesome 3800 series II and III.
I have no doubt that part of the reason why GM stuck with Oldsmobile and Chevrolet V8s during the 1980s was that they could meet emission standards easier than the other divisions engines. The Chevrolet V8 was able to meet emission standards with a carburetor until 1988 (in 1989 all SBCs became EFI) and the Olds until 1990 with a carburetor. Albeit the Olds 307 needed all the help it could get to pass by then, and it only did so just barely. While the 307 lost power and performance through the 1980s to meet emission standards, the Chevrolet 305 was actually able to increase performance while meeting the EPA standards.
Undoubtedly cost was the ultimate driver of all of almost all of these decisions too. We had a comment left here a while back about the internal bidding process at GM; divisions bid for supplying others with engines. Chevy almost invariably had the lowest bids.
That’s not surprising, considering its vast production capacity for its small block engines. And after 1980 or so, as GM’s market share was declining, and big car sales were in a swoon, there had to be massive excess capacity at Chevrolet. And presumably at most/all of the others.
It would be interesting to know what Chevy’s max production capacity for small block V8/V6 engines was, and in what year they built the largest umber of them.
I wholeheartedly agree that cost was likely the biggest driver for the selection of those to engines, but I am sure there were other considerations like emissions. I mentioned that cost was likely the biggest factor in my comment below in response to CAFE comment. Chevrolet undoubtedly had the lowest cost for engine, partially due to its simple design (which doesn’t mean it was inferior in design) and its massive production capacity. Not only were SBCs made in various US plants, but GM of Canada only produced one V8 engine, the Chevrolet V8. The Canadian produced engines were no longer limited to Canadian market cars only by the late 1970s.
The Pontiac engine had the largest cooling system in the industry. This was great in the 1960s for selling to people who wanted cars that would not overheat, (such as people in the Southwest and South, people who towed large loads, people who needed to drive up mountains at high speed on the new interstate highways, and operators of airport limos who did lots of idling). The problem is that it took too long to get to operating temperature, where emissions would be lower than at startup, so it had a hard time meeting newer emissions standards.
There was also the matter of the Buick V6 being that division’s best engine, by far once they smoothed out the early odd-firing issues. There was the possibility of V6s replacing the V8 across the board at the time of the second oil crisis, and the Buick V6 put GM a step ahead of Ford and Mopar. As someone stated a few days ago (here? or maybe on /r/cars?) the 90deg Buick should’ve been the corporate V6 with the 60deg Chevy 2.8 used only where space necessitated it.
I was told back in 1980 that one of the reasons the Buick V-8 was dropped was to enable the Flint Buick engine plant to make more V-6’s. Buick V-6 demand became so high that for a period of time the engine was also built at the Lansing Oldsmobile engine plant.
For the most part the larger engines weren’t shared. There are a couple of minor exceptions that I can think of. For 1975, the Pontiac 400 was available in the Oldsmobile 98 and Custom Cruiser as a credit option. However, there really is no small or big block Pontiac V8 (discounting the low deck 265-301). Furthermore, the 400 was a small main journal engine, unlike the larger Pontiac 421-428-455 engines which used large main journals.
The Oldsmobile 455 (and 403) were also used by GMC in it’s Motorhome. But I guess GMC didn’t really have their own V8 to use, unless you consider the 454 a GMC engine. Lastly, there was the Canadian market Pontiacs that used Chevrolet Big Blocks.
I don’t think CAFE had any major effect on GM switching to divisional engines. If any government regulation did, it would be the EPA emission standards. With more engines, it required more certifications. However, IMO, the biggest reason was cost reduction. GM was going attempting to reduce costs during this time and it makes a whole lot more sense to have corporate engine versus divisional engines. Regardless of government regulation, I believe that under the major restructuring of GM under Roger Smith, it would have happened regardless of outside Government regulations.
The Olds 455 was used in the Motorhome because it was part of the front-drive Unified Power Pack that made the low floor setup possible. A Chevy 454 would’ve required rear-drive through a TH400 or Muncie which would’ve made the whole thing much more like a typical body-on-frame RV.
For whatever reasons the Cadillac Eldorado’s 500cid engine wasn’t used, either production capacity, divisional exclusivity or the extra power wasn’t deemed worth the extra fuel consumption.
I am aware of the fact that the GMC motorhome used the Olds V8s due to the UPP. However, it was still an exception of division using another’s large V8. My point in bringing up the 454 was that this would have typically been the large displacement V8 that GMC used, not the Olds 455. I also realize that the 454 was not a practical option for the UPP. However, if GM really wanted to, I am sure they could have made a version of the TH-425 that had a Chevrolet bell-housing and adapted the 454 to fit into the chassis (they adapted the Cadillac V8 for the UPP albeit it used the same bellhousing as the Olds). Obviously though this would make little sense in terms of cost for a low production unit, especially when the 455 UPP was ready to go and required no additional development costs. I suspect the Olds engine over the Cadillac was used due to production capacity, cost and durability.
I have fond memories of my Mom’s 1961 Buick Special (GM Y-Body) coupled to the 215 cubic inch Aluminum V8, often seen in Buick, Oldsmobile and Pontiac (B-O-P) applications. Which begs the question: Why did GM produce multiple, often incompatible variants of major components that were unique to certain divisions? Not only did that strategy fail to take advantage of economies of scale, it actually added millions of dollars to GM’s costs, due to the cost of designing, purchasing and stocking production and repair components for each individual model of engine or transmission. Some of this may have its roots in the origins of GM’s divisions as formerly separate companies, but that was a distant memory from decades earlier when unique division components were common practice. When GM tried to solve the problem in the 1980’s by reducing the number of variants, by putting Chevy engines in Buicks, Oldsmobiles and Pontiacs, they made the mistake of trying to keep it secret, triggering lawsuits by the hundreds. If they had disclosed the facts upfront, it would have been a non-issue, but by trying to do it clandestinely, they looked like they were up to no good. Kind of like when they made the mistake of hiring private detectives to dig for dirt on Ralph Nader, making him much more famous than he had any right to be, even after his flawed book: “Unsafe at Any Speed” .
Another author pointed out that in the 1950s GM divisions actually thought of each other as major competitors. There definitely was anxiety that the corporation would get into Sherman Antitrust Act trouble, a la Rockefeller’s Standard Oil. As GM’s market share declined, Japanese competition was increasing and costs were rising, antitrust action seemed less likely.
GM sales were so robust and most divisions, specifically Buick, Olds and Cadillac had so few platforms each division had enough demand to allow for their own engines. In 1972 Buick had only three platforms…..Skylark A. LeSabre B Electra C and Riviera C…ll using only two V8 engines…350 and 455. Buick sold 679,000 vehicles that year, enough cars to keep Buick’s engine plants humming.
Interesting discussion. I hadn’t thought about this before. Starting in the ’20s, GM based brand identity on engines. Visible identity in bodies came later, starting with the ’35 Silver Streak, and was never as precise as engine identity. Chevy never had its own permanent styling cues.
Most companies in the ’20s were outsourcing at least some of their engines from Continental or Lycoming, and everyone, including GM, was outsourcing bodies from a few coachbuilders.
Very good article Tom. This is not a simple topic to research, GM did not make its engine sharing simple, particularly during the late 1970s. There are a couple of things that I can add.
Buick did share its 350, albeit to a smaller degree than say Oldsmobile, in the late 1970s with Pontiac. After 1977, the Pontiac 350 was replaced with either the Olds V8 (VIN code R) or the Buick 350 (VIN code X) in its full-size line until 1980. The 1980 Pontiac brochure only lists the Olds 350 but part catalogs show the Buick 350 was also available. The Skylark didn’t get the Chevrolet 305 in 1975, the 305 wasn’t introduced until the 1976 MY. My sources show that the 305 wasn’t available in the Skylark until 1977.
On the Pontiac V8 engines, it should be noted that the Pontiac 400 was offered as a credit option for the Oldsmobile 98 and Custom Cruisers 1975. This was meant to be a more economical option than the big Olds 455. Of course, we can’t forget that the Canadian market Pontiacs used Chevrolet V8 engines, almost exclusively, from 1955 on. The only exception (for full-size Pontiacs) was the 1971-76 Canadian Pontiacs, which were a hodge-podge of Pontiac V8s and Chevrolet V8s depending on what model was ordered. From 1977 to 1985 Canadian full-size Pontiacs reverted to using the Chevrolet V8 engine line-up. In 1986, they started using Olds 307s in Parisienne in place of Chevrolet 305s.
Oldsmobile mostly used only Olds V8s, with the odd exception (like the Pontiac 301 in the early 80s, the Pontiac 400 credit in 1975, or the Chevrolet 350 in 1977). The lesser models like the 1978 A-bodies and the Omega did see some Chevrolet engines though. After the 1977 Chevrolet 350 scandal, it seemed that BOP V8 powered cars, in particular the full-size models, generally defaulted to Oldsmobile V8s. The 307 became a very prolific engine during the 1980s and was used by all five car divisions. I don’t know for certain, but I suspect that there was a surplus of Olds 307s in the mid to late 1980s, which is why GM started using it in more applications around that time. As I had already mentioned, 1986 the Parisienne sedans started using 307s in place of the 305 Chevrolet. Also, mid-way through the model year, all GM B-body wagons used the 307 exclusively. Formerly, Chevrolet and Pontiacs wagons used Chevrolet 305 engines. These wagons used the 307s exclusively until 1990. Many Canadian market 1987 Caprice sedans also got 307 Olds V8s. 1986 also marked the year that the D-Body Cadillac Brougham got the 307 Olds as its exclusive engine choice. In 1990, the Chevrolet 350 LO5 became optional on the Cadillacs. In 1991, the Chevrolet 305 LO3 replaced the 307 in the Cadillac and the B-Body wagons.
For Chevrolet, like you mentioned, it almost always used Chevrolet V8s. Besides the Olds 350 diesel, the other exceptions are the 1986-90 Caprice wagons and some Canadian market 1987 Caprices, both of which used the Olds 307 V8. To my knowledge, the last year of the Gen 1 V8, was 2003, where it was offered in the Tiltmaster trucks as the 350 Vortec (Gen 1 engine). In 2002 you could still get the Gen1 Vortecs in the Chevrolet Express/GMC Savanna vans.
Also on Chevrolet V8s, they were used much more often in the Canadian market. Not only did Pontiacs generally use Chevrolet V8s, but many Buicks and Oldsmobiles did after 1977 as well. For example, rather than the Olds 307 used in the 80s GM A/G-bodies, most Canadian market A/G-bodies used 305 Chevrolets instead.
Thanks for the feedback, Vince. As you mentioned, this was a difficult post to research (many, many hours poring through brochures). GM wasn’t exactly transparent about this (at least not before 1977).
Plus, to your point engines were sometimes offered as “off the books” delete options. Some powertrains were advertised in brochures but never actually ended up being sold, while others were sold but not officially listed in the brochures.
All this coyness seems quaint now, since we are all used to “GM Engines” but clearly it was a big deal to GM back then. An interesting time, to be sure!
Here’s a minor instance of pre-WWII GM engine sharing: the 1934 LaSalle chassis is completely shared with the concurrent 240 ci straight eight Oldsmobile Eights. LaSalle was due to be dropped until that stellar, progressive design was presented to the Bod. The reprieve was granted based on sharing as much with other GM makes as possible.
For 1935-’36, the LaSalle continued the sharing, simply increased the stroke 1/8 for 248 ci. The Oldsmobile blocks and components were delivered to the Cadillac plant for finish machining, a few changes to fit it to the LaSalle under hood space…and no doubt so they could claim it as Cadillac’s own.
Something similar happened across corporate lines with the “VW” engines used in early Dodge Omni/Plymouth Horizon. VW sold short blocks with cranks to Chrysler who then completed the engines with their own components.
They were complete long blocks. Chrysler only added its induction, ignition and emission systems.
And mini Torqueflite. I think the manual trans was from VW. No idea what they did with manuals after the VW engine period. I think there was a short period of Peugeot engines before the 2.2 came out and Chrysler put it in everything.
I had ’78 and ’88 Horizons, both automatics. The 2.2 enabled the ’88 to be much longer geared and quieter on the highway, plus it had gained a lockup torque converter by then.
I recall the manual transaxles were Chrysler designs, built by New Process Gear. (T-III cars and later Shelby models, IIRC, got Getrag boxes.) The 1978-83 4-speeds were VW.
Peugeot engines ran 1983-6, only available with manual transaxle and not available with A/C.
That too is my recollection. However I believe they were unique and built to Chrysler specs, not just long block VW engines. 1700CC’s when VW’s were 1500-1600, but might have been lower compression and I don’t know about cams. And I have no idea what spec the bellhousing was, VW, Chrysler or itself.
Presumably, VW: the early Omnis used VW-sourced transaxles.
> Oldsmobile was also the sole maker of passenger diesel engines for all of GM in the 1970s and 1980s
Arguably, the Chevette Diesel is an exception.
The Buick V8 found its way into the Kaiser-era Jeep Wagoneer. I can’t think offhand of any non-GM vehicle that had Pontiac or Olds power.
A mention should perhaps be made of Canadian Pontiacs using Chevy V8s for decades before 1982.
I’m unclear on whether engines like the Northstar or the short-lived Blackwing, even if they were Cadillac-specific, would qualify as being Cadillac-produced. From what I understand, Cadillac or any other GM division didn’t really produce any engines after 1984 or whenever GM Powertrain was created during Roger Smith’s tenure. There may have been division-specific engines after that, but those divisions didn’t have their own engineering staff to design it. Or did they?
Some other RV manufacturers, most notably Revcon used the UPP with its Olds V8.
There were a high percentage of 1979 Pontiac Bonnevilles equipped with the Buick 350, to dispute the statement that Buick was a stingy lender. Have also seen Buick 350’s in Pontiac Ventura’s.
Why was it easier for the Buick V6 to pass US emissions standards unlike the Buick V8 and would a hypothetical Oldsmobile V6 have possessed a similar capability of meeting US emissions standards as both the Oldsmobile V8 as well as the Buick V6?
As for the Pontiac V8 and Trophy 4, did it influence any other carmaker’s engines apart from possibly International Harvester?
That’s a great question. The Buick V6 was originally based on the Buick 215, which developed into the 300/340/350 (in cast iron, except for the cylinder heads of the first-year 300). Perhaps the Buick wasn’t such a dirty engine after all and it did come down to cost, as Paul said above. They also might have updated the cylinder heads on the 3.8 when they converted it to an even-fire engine, but I don’t have any experience with Buick V6s.
Oldsmobile did make a non-hypothetical V6, one that I almost forgot about – the unpopular 4.3L diesel (1982-85). Maybe they should have tried converting it into a gas engine 🙂
Indeed, would though a petrol version of the Oldsmobile V6 diesel have been an adequate alternative to the Buick V6 or would a better solution have been a non-alloy V6 Oldsmobile version of the all-alloy 215 Oldsmobile V8 (that was said to be very similar to the 215 Buick engine yet not identical)?
Cost would definitely be a factor with the Buick V8, in retrospect it would have probably been better for GM to further develop it along the same lines as the Buick V6 and have the Buick V8 carry over the developments the Pontiac V8 received at the latter’s expense to survive past the early-80s,
The advantage of the Buick V-6 was its combustion chamber design, which had a saucer-shaped section in the head matching up with a depression in the top of the piston. This chamber design was introduced for the initial Buick 215 as a way of reducing its octane requirements for the use of regular gasoline, but it later turned out to have the important side benefit of reducing hydrocarbon emissions. Buick shared this combustion chamber design with the Fireball V-6 (although the V-6 chamber wasn’t machined), and later adapted it for the Buick 400/430/455 engines, by which time its benefits for emissions control were a greater concern.
(Oldsmobile did NOT use the same chamber design for their aluminum 215; they insisted on developing their own version of the heads with a wedge combustion chamber more like the big Rocket engine. However, they later adopted a conceptually similar chamber design for their later V-8s.)
Both of the later Buick iron V-8s shared the same chamber design as the V-6, but GM ended up having greater need for the V-6 corporation-wide, and so that became the production priority.
Great read. I was following along and thinking uh oh Tom missed the GMC V8.
…and then he plinked the GMC. LoL
That leaves the Curbside Contrarian to mention that (not counting Chevrolet’s ’18 and Pontiac’s ’32 early V8 false starts as quits) that possibly Oakland Division quit its (Viking)V8 first?
Here is another rare one. In 1973 a handful (about 1,000) of Chevrolet Impalas were built with airbags. They had Oldsmobile Dashboards (required for airbags) and engines, but Impala sheetmetal and interior trim. All were green and mostly sold to fleet buyers, and one appeared on Seinfeld.
Some Buick Electras were built with the airbags, in 73 or 74. I was not aware of any Chevys being in that experiment.
Yep, it’s true. See for yourself.
Interesting article Tom-if I remember correctly the Pontiac Ventura used the Chevrolet 250 six and 307 v8 when it debuted in mid year in 1971, by 1972 it was using Pontiac’s 350 V8 engine until I believe 1977 when it was using the Chevrolet 305 V8. I think a 350 was available that year but I am unsure if it was Pontiac’s or another divisional engine.
I remember seeing Cadillac advertisements in 1980 or 1981 offering a V6 (Buick ) in certain models-can anyone confirm this?
Yes, Cadillac did use the big 4.2L Buick V6 for some years. But Tom did limit this to V8 engines.
Starting in 1964 Olds and Buick A bodies used the Chevy 230 six.
I have seen the old 225 odd-fire Buick V-6’s in Buick A bodies as late as 1967. Pontiac briefly had a 215 cubic inch version of the Chevy 6 before the OHC.
Yep, the ’64 and ’65 Buick Special/Skylark and Olds F-85 came standard with the Buick 225 V6. Olds switched to the Chevy 250 in ’66, but Buick stuck with the V6 until ’68.
Pontiac had the Chevy 6 in ’64 and ’65 until switching to the OHC 6 in ’66.
The V-6 intake distributes air more efficiently than the V-8 intake, so emissions are reduced. And to answer the below question, Cadillac did offer the Buick V-6 in some models.
The bored out 4.1 Buick V6 with 4bbl was offered in DeVilles for a few years starting in the early 80s, as a credit option- Not sure about the Seville/Eldo line. IIrc, it had the same hp and economy with better torque (and reliability) than the HT4100. Sometimes skinflints win.
The Buick V6 was a MUCH better choice than the awful 4100.
Wikipedia says the 4.1 V6 was offered in the Eldo/Seville in ’81 & ’82. The diesel V8 was standard on Seville in ’80-1. It says the Cadillac 368 V8 had 145 hp, versus 180 for the Olds 350 in the same year. Both were fuel injected.
I sure remember the late-1970s fuss about this in the newspapers–but learned a whole lot today. Thanks for gathering all the info.
1) I saw the first illustration, and my reaction was, “it’s the Visible-V8!”
2) From the other end of things, it’s interesting to see the 1950s SAE reports where each division proudly presents its engine’s design goals, features, etc.:
Is there a central source for all these papers?
George has them all stacked in his living room. 🙂
Excellent story, Mr. Halter, I appreciate the research involved. As an old guy that spent the late 60’s and early ’70’s behind a GM parts counter in Canada- I seem to recall 1956 and 57 heavy duty GMC W99 tandems that had a version of the Buick 322 nailhead. I believe it was only for the two years.
Yes, but only in Canada. There was a heavy duty version of the 322 Nailhead used by Chevy in their largest trucks in ’56 and ’57, and the engine was also used in similar Oshawa built GMC’s. Heavy duty GMC’s built in the U.S, used a version of the Olds V-8 from ’55 to ’59. Chevy also used the GMC 637 V-8 in their 90 series trucks.
Yes, found one for sale in 1958..
I’d give them a call except… 6 digit phone number!
I don’t think the 1970’s engine scandal was started by “secrecy” or “lawyers” but by the fact owners paid extra for an Oldsmobile Rocket engine as listed on the Monroney sticker and later discovered it wasn’t under the hood!
In 1949 – 1954 Olds not only had the big Olds 98 models but also the smaller Chevy body models labeled Olds 76 with a flathead Olds straight 6 or Olds 88/Super 88 with the 98’s big V8… The little Olds 88’s becoming King of Nascar stock car racing and dragstrips about 1952 – 1955… taking over from Hudson’s big flathead straight 6’s, Chevy OHV straight 6’s, and Ford flathead V8’s…
When Pontiac, Olds. Buick, and Cadillac big block engines ceased production there was just plain a shortage of V8 ENGINES to power vehicles and Chevrolet couldn’t make enough so Olds got to hang around a while longer making cheap V8’s…
When I worked for GM in mid 1960’s they had 52% of the market and all the other makers shared the other 48% so the Govt was threatening to break GM up as a monopoly like it did to AT&T unless it sold fewer cars. Problem was buyers wanted GM cars, especially after ’57 Chevy and GTOs came out. And dealers wanted to sell them.
This piece got me thinking about what the last year was that the GM divisions had their own automatic transmissions (i.e. Buick Dynaflow) rather than using one of the corporate-wide THM units. The last of these I thought was Chevrolet’s Powerglide in 1973, forgetting Saturn had their own 4 speed automatic for the S series through 2002.
The Buick-Olds-Pontiac (BOP) divisions used a two-speed automatic that wasn’t a Chevy Powerglide for years. It was called the “Super Turbine 300” and was often fitted to the BOP Y-Bodies (Buick Special, Olds F85 and Pontiac Tempest) in the early sixties. My Mom had a 1961 Buick Special with the 215 V8 equipped with the ST 300 automatic. As I recall, my Dad blew up the tranny towing a U-Haul loaded with an old wooden desk that presented too much of a load for it.
ST300 went on line in ’64; it was a tough box. Squeezed out by THM 350 circa 1969. The two were of similar enough architecture they no doubt shared “dna” in manufacturing.
Mom’s Special had a “Baby” Dynaflow.
Olds had a “Junior” Slim-Jim.
Tempest’s Tempestorque was based on Corvair Powerglide.
Oldsmobile called these the Jetaway
I’m pretty sure they had a switch pitch stator, so a little better than a Powerglide.
Jetaway lost the “switch pitch” feature I think in ’68 and Pontiac’s version never had it.
The ST300 did not appear until ’64. Your mom’s ’61 Special had that awful and short-lived Twin Turbine. All GTO’s/LeMans/Tempest V-8s in 64-66 with automatic had the ST300 and many people today think they had Powerglides!
The automatic in the 1961–1963 Special and Skylark was Dual-Path Turbine Drive, which was wholly unrelated to either Twin Turbine or ST-300. It was an unusual two-speed automatic with only a single planetary gearset (reverse was provided by using the torque converter stator as a turbine!) and a split-torque high gear. It was dropped for 1964 because it didn’t have the torque capacity for the iron 300 cid engine.
Great article! Interesting but complicated topic that’s never the less easy to read due to clear writing and funny lines (O negative-universal donor!). Good choice of pictures, too.
I’m no expert on this topic, but I tend to think that divisional engines contributed to GM’s market dominance in their glory years. They were the first and most successful having multiple brands and the perception of better engines surely motivated not a few customers to pony up to get to the next rung on the GM ladder. And there was some truth behind it. The SBC was a good engine, but I think the Pontiac, Olds, Buick, and Cadillac V8s all had legitimate virtues.
Very interesting, and effectively concise given the complexity of the topic. I remember the scandal, particularly as it related to Olds and Cadillac with their perception of special “Rocket” engines in the case of Olds, and of course Cadillac-ness for the latter. My own 1981 Firebird, with the California-market Chevy 305, seemed special at the time (my only SBC, in fact my only V8) but in hindsight a 301 Firebird would have been more special, as the last of its breed.
I worked in auto parts for years, and have seen Caprice station wagons of the ’80s list a 307 Oldsmobile engine as an option
Fairly common. I suspect they were trying to use up the supply of 307s before the end of 1990, and didn’t sell enough Fleetwoods and Olds wagons to do so.
A friend’s dad was enraged when he discovered his Olds had a Chevy engine. I was greatly amused at his anger, and asked him why he wouldn’t want the superior and cheaper Chevy 350 in his car instead of the 350 Olds engine he expected. He couldn’t really come up with an answer that made sense. I owned both, and while there was nothing wrong with the Olds 350s that were in my ’71 and ’72 Cutlasses, the ’72 Chevelle with a Chevy 350 I drove for a loaner while the ’72 had an electrical issue resolved (It’s nice when your dad went to school with the owner of the dealership) was superior in every real way than the ’72 Cutlass was, except maybe for looks. When the Cutlass finally got straightened out, I missed the Chevelle, it ran great. Even after a little carb tweaking, the Cutlass never ran as good. And by the time my mother and sister’s ’73 Cutlasses arrived, the ’73 Chevy 350 in the Camaro and Chevelle was noticeably better running than the Olds motors were. IMHO, the best performing of the early 70’s small block V8s was the Chrysler 340/360 4 barrel engines. Rated the same horsepower, 245, in 1974, the Mopar was always a little quicker. A friend’s 318 Challenger was barely slower than another neighbor’s ’74 Z-28 Camaro. My ’74 360 Roadrunner (15.21 bone stock untouched, 14.20’s to 14.4 that day) crushed the Z28 at Milan Dragway on opening weekend in 1975. On paper it should have been very close, but it wasn’t. As long as I didn’t blow the tires away, I won by at least 3 car lengths, and if I launched decently, it was more. Add to the fact he couldn’t cut a light if his life depended on it, it just made it more humiliating for him as he really thought the Z28 was “fast as hell”. I had the Roadrunner into the mid 14 second range before it had 1500 miles on it, and before it was a year old, I ran my first 13. It was barely a 13 second ET, but it was a 13. All it took was a little carb work and some timing adjustments and some bigger tires. The tires were the only real expense. Once that car got it’s “new car bugs” out of it, it was bulletproof for the next two years when I stupidly traded it for my disaster on wheels ’77 Macho Power Wagon. I’m pretty sure the ‘Wagon is gone, but the Roadrunner is alive and more than well in the Las Vegas area with a 440 stroker motor making big power.
A lot of people would disagree with the statement that the SBC 350 was superior to the Olds Rocket 350, especially in longevity & durability. Cheaper, yes it was.ou get what you pay for.
A lot of people are just wrong then. I worked on cars for a living in the mid to late ’70’s and the Chevy 350 was about as bulletproof as an engine could be. The Rocket 350 wasn’t bad at all, but the Chevy 350 was better.
When I was chasing a sump gasket for my Buick 350, it took a phone call to the vendor to ensure I got the Buick gasket. “But the book says this one will fit” was all I got online.
Excellent explanation of the bewildering question mechanics had to answer when they had a GM car in for repair in the 1970′-1990’s. My mechanic friend who ran a garage then had to check VIN more than once to determine what division engine he had to get parts for to do the job.
GM painted themselves into this corner. The division exclusive engines were a legacy of the way GM was organized in the beginning. The divisions developing and manufacturing their own engines was promoted as superior to those other car makers who either utilized a common engine family throughout their various nameplates or worse, bought proprietary engine from Continental or Lycoming. While GM held the majority of the market, they could afford that luxury.
I get the impression that back in the old days GM was pretty much the ‘umbrella’ under which five separate companies operated. 🙂 Very different to Chrysler and Ford.
When dad took his Cutlass Supreme in for an oil change, not at a GM dealer, invariably they would pull the Chevy oil filter from stock and have to go back for the Olds part. That was how common the “Chevy engines in Oldsmobile” negative publicity was back then.
The Olds diesel made it into Chevy pickups and I even got to drive a Checker powered by one. Buddy of mine still has the truck.
In my uninformed and humble opinion, the engine sharing decision was a debacle. Now, it had nothing to do with the performance or quality of the shared engines; it was purely a matter of perception, but GM had deliberately cultivated that perception.
You see, we know that basic platform sharing was going on at GM at least as far back as the mid 50’s – there were cosmetic differences between the makes, but the distance between a 55 Chevy body shell and its Pontiac brother weren’t very big.
So, this forced the question: why am I paying extra for a Pontiac/Olds/Buick? (At this point in history, we can leave Caddy out as no one ever asked that question about Cadillac).
There were, at first, two valid answers. Interior features and material quality and engines of perceived better engineering and quality than Chevy. Then one day (to try and summarize a thousand little things in one vastly over-simplified phrase), “Chevys got leather…and stereo radios… and A/C.” Now, in the 70’s when the interior quality of GM cars started to falter, the perception was that Olds and Buick fell farther than Chevy – as their interiors were no longer superior to Chevy.
So what did that leave to justify why you weren’t a fool for having paid considerably more for that Oldsmobile over a visually almost identical (inside and out) Chevy. The answer is obvious:
It’s got an Oldsmobile engineered drivetrain. That’s worth the the difference right there!
Wait. What? You must be kidding.
@#$&!
Next time I shop on price and if a Caprice is $2 cheaper, I’m buying that. Why pay more for same thing?
GM cars shared basic bodies in sometimes baffling ways with one brand like ’54 –
’56 Buicks for example having two basically very different bodies but then a lot of same bits like dashboards, tail lights, suspensions etc. – until the emergency 1959 replacement of everything. But under the 1959’s there were completely different frames and suspensions. I don’t know how many, but Chevys continued the new for 1958 X frame and Pontiacs had a perimeter frame. (I think)
Another historic GM car nerd story worth untangling. The Car Style Critic guy has done some of it.
The earliest example of engine sharing I can remember at GM was in 1968 When Oldsmobile and Buick started using the Chevrolet 250 ci six as the base engine in their intermediate models. Buick sold the tooling for the V6 to AMC, Pontiac used their OHC 6 through 1969 and then switched also to the Chevy 6.
1964-1965 Olds F-85/Cutlass used the Buick 225 V6 as its base engine.
When I was a teen, our church had an old ’58 GMC church bus that had a Buick nail-head in it. I can’t swear it was original, but I believe it was.
I recall seeing that some GMC trucks of that era used Pontiac V8 engines.
Buick nailheads were used in industrial applications, surprisingly.
The jet engines of the SR-71 Blackbird were started by nailhead Buick V8s for many years.
Some Flxible buses used Buick power, though I don’t recall if that was Nailhead or the old Fireball straight 8.
I think that there are multiple definitions of better. Is better having more potential for more power? Is it more power now? A better torque curve for more perceived power, even if not on the dyno? Is it smoother running? Longer lasting? Better sounding? And more I’m sure.
Now I’ve only taken apart a handful of Chevy engines from the 60s, and none later, but they all had significant wear in the cylinder bores. There were some I’m not sure would have cleaned up at 20 over. Did other GM engines, Olds specifically, have that issue? If not, it would suggest they were longer lasting, which is kind of a big deal.
Pretty sure everything had bore wear in that era…low-tension rings weren’t a thing, and many engines used plain iron or steel piston rings with no coatings. (Only one I can think of offhand that used coated rings was Chrysler, and then only on a few engines.)
And what passed for engine oil back then had terrible cold-flow properties, and a cold-started carbureted engine immediately soared to high RPM on the fast-idle cam while the closed choke dumped raw fuel into the engine to wash off whatever oil managed to reach the cylinder walls…
I had an 87 caprice classic wagon with the olds 307.. Factory car. Bought from the original owner
A minor point about the aluminum 215: Buick did NOT sell the tooling for the aluminum V-8 to Rover. Rover bought a manufacturing license for the engine and then spent £3 million on their own tooling. They knew they were going to need make various changes to the existing design (and their license allowed them to do so), and they didn’t want to be handcuffed by the need to use the existing Buick tooling.
That explains how Rover was able to work all of the bugs out of the design that GM couldn’t or wouldn’t fix. To be fair, if you only produce an engine for two or three years before killing it, you barely have time to find the problems, let alone fix them! No matter how thoroughly you analyze the design, or how long and diligent your test program is, you never really find all the bugs until you start producing parts in volume and the products end up in the customer’s hands! GM was and is famous for designing and producing new engines for only a couple of years, then killing them off just as, or, more often than not, just before the engineers get the bugs worked out! The Buick/Olds 215 V8, the Corvair flat six, the DeLorean OHC I6, the Quad 4, and most recently, the LL8, a.k.a. the Vortec 4200 I6. Only GM seems to be afflicted with this disease, since for years, with their dominant market share, only they could afford to waste the kind of money it takes to develop a “clean sheet of paper” engine design, then throw it away because they don’t have the patience to follow through and finish the development process. I suspect that the “bean counters” that have traditionally been dominant in management at GM have something to do with it, but I can’t either prove that statement, or explain why GM keeps doing it.
Roger Smith, the GM CEO and penultimate product of GM’s bean counter culture, took this idea to its logical conclusion, by creating a whole new division from scratch, complete with its own factory and dealer network, only to have one of his successors flush the whole thing down the toilet about twenty (20) years later! I refer, of course, to Saturn!
I suspect that Buick engineers might have quibbled with the contention that they abandoned the 215: In essence, they just switched it from aluminum to thinwall iron, keeping the same architecture, but taking out a lot of the cost and many of the problems. There was a weight penalty, but the iron 300/340/350 was still pretty light, in the same realm as the Ford 260/289/302, and Buick went on to use it for 16 years, which was not a bad run.
Rover and British Leyland engineers said in the seventies, they’d occasionally talk to GM engineers and executives about the aluminum V-8 (such as to inquire whether GM would object to BL using the V-8 in products for the U.S. market), and the GM people were always sort of amazed that the British were still bothering with it — “You’re still using that old thing?”
So it was basically the bean counters that prevented GM from ironing out the bugs in the 215 BOP V8 and held themselves back from possessing an engine that could have been used in GM vehicles for a similar production as the related Buick V6 or SBC V8?
Did wonder why the then independent Rover company was able to successfully iron out the bugs given its low-volume status and how many cars it would go one to power, what GM wouldn’t or couldn’t be bothered do themselves.
Curious to know what the background was behind an ill-fated attempt by GM to buy back the Rover V8, because it seems elements to the story have been conflated with how GM acquired the tooling of the Buick V6 from AMC years after the latter bought Kaiser-Jeep.
GM had no need to buy anything back from Rover. Rover (and subsequently British Leyland) didn’t buy the tooling; they bought a license to manufacture their own version of the Buick design for their own use, with fairly broad rights to make changes to it. When they bought the manufacturing license, GM also allowed Buick power plant design chief Joe Turlay, who designed the engine, to spend a year or so as a Rover consultant prior to retirement.
So, Rover had copies of all the design and engineering documents, the direct on-site consultation of the engine’s actual lead designer, at least 39 complete Buick engines for reference and testing, and the budget and contractual leeway for all-new tooling. If you’re going to try to improve on a flawed existing design, that’s a pretty good foundation. Rover was also able to spend about two and a half years setting up tooling and production, and then introduced the V-8 in the relatively low-volume P5 so they could get the line running up to speed before installing it in the P6 and subsequently the Range Rover — unusual luxuries when it comes to engine development.
Buick DID sell the tooling for the V-6 to Kaiser Jeep in 1967 and then bought it back about seven years later. After AMC bought Jeep, they stopped building the V-6 and packed all the tooling in Cosmoline for storage, so it was just sitting around.
After restarting production of the V-6, GM had no need for and, by every account I’ve seen, no interest in the aluminum V-8. The V-6 was much cheaper to make, was far less troublesome to manufacture, had greater displacement, returned better fuel economy, and was more compact. The V-8 was somewhat lighter, but not that much, and not enough to be worth its substantially greater cost. In any event, need for the V-6 quickly eclipsed need for the Buick V-8, which was, depending on your point of view, either a V-6 with two extra cylinders or a cast iron version of the 215.
Did find the idea strange, however tempting it would have been to use the all-alloy V8 in GM’s H platform models.
James Taylor relates Rover were also offered the rights to the Buick V6 and even when Kaiser-Jeep gained a licence for the Buick V6, were not completely put off from a cast-iron V6 based off of the Rover V8 for use in Land Rovers and were said to have figured they could make their own before they lost interest by the time of the formation of BLMC.
Rover also had plans to develop an advanced replacement for the V8, utilizing design features from the Rover P10 engine that unfortunately never had a chance to get off the ground.
They certainly wouldn’t have sold the tooling since the whole point of the V6 derivative was to be able to use much of the same tooling. It seems that a lot of people don’t understand that the biggest investment by far in building engines are the giant transfer line machines, that do the machining on the blocks (and heads). These machines are set up for certain bore centers and other key dimensions, and can thus be used by various engines using the same basic block, or they can be modified to be used on other engines with the same bore centers.
The V6 used these same machines, as the block was essentially 3/4 of the V8. And at least as important, or more so, the same machines were of course used on the iron 300 CID V8, which became Buick’s primary smaller V8 for years.
My assumption is that selling off the V-6 tooling to Kaiser Jeep was that by 1967, Buick had much greater need for V-8 engines than for sixes, and thus it was simpler just to buy Chevrolet sixes for those who still wanted them. The reason for the demise of the Buick V-8 14 years later was probably the inverse; GM needed all the V-6s they could build, the V-8 was expected to be extinct within a few years anyway, and Chevrolet and Olds could supply what was needed in the meantime.
This is an area where distinct engines sharing tooling can be a double-edged sword: If you have a lower-volume variant, there’s much less investment if it shares tooling with an existing volume engine (e.g., the Pontiac Trophy 4), but if volume is TOO low, it may be seen as just clogging up the production lines that are more urgently needed for something else.