(Updated 5/18/2026) I’m not going to add much commentary to Road and Track’s first look at the new Olds Diesel (Delta 88 Royale) in the November 1977 issue, and a follow-up drive (although not a full-on test) of a 98 in the May ’78 issue. The first one examines the origins and development of the Olds diesel, and both have some good commentary, including questions about its economic viability as well as the unknown reliability. As it turns out, it was precisely those two issues that killed the Olds diesel.
But for 1978, the performance was pretty decent, and an honest 25 mpg for a full size car was unparalleled by any other domestic maker then. It really seemed like these had a future…
The second article has more serious questions about the economics and reliability. Given the additional $750 cost of the diesel, it would take some 100k miles to recoup the cost versus the 260 CID gas V8, an engine with similar performance. And then there was the question of its design life of some 100-125k miles. As if…
I have vivid memories of auto, motor und sport testing one of these, and raving about it. Big American cruisers (“Strassenkreuzer“) were in again in Europe, largely in part because the dollar was cheap, making them affordable, as well as the enduring allure of something so utterly different. But of course the fuel bills were an issue, and the Olds diesel solved that, rather spectacularly. To be able to roll down the autobahn in a big American car while only using some 10L/100km (24-25 mpg) was a dream, given the much higher fuel costs in Germany. Its performance was considered quite good, keeping in mind that most European cars had much smaller engines than the versions exported to the US. A 0-100 kmh time of some 15 seconds was quite decent. As far as I know, a goodly number were sold over there, but how that all turned out is another matter.
Related CC reading:
1980 Oldsmobile Delta 88 Royale Coupe With Diesel V-8 — Disco-Era Diesel Survivor
1978 Oldsmobile Delta 88 Diesel — In Defense Of The Olds 350 Diesel V8
Car and Driver also had a rather positive write-up of a Delta 88 diesel, similar to the featured R&T road tests here. It was December 77 (or 78).
“600 miles on a tank of fuel” in big-car comfort, in GM’s excellent full-size cars.
I ate it up at age 13. After all, if Car & Driver said it, it was (probably) true!
I also liked Road and Track, and read every issue (though I didn’t buy or subscribe). It was during this time of my life that I jettisoned Motor Trend. And Road Test had stopped printing (I liked their sales report on the last page).
I did not know about the popularity surge these had in Germany. I wonder if the diesels fared better in that market, which has been known for much better maintenance habits than usually displayed by US customers raised on the anvil-like qualities of 40s-50s US stuff, especially from GM.
Here’s the thing. I liked Car & Driver because I found it well-written and not shy about bashing cars and making ‘clever’ comments. Road and Track was good too, but a little too snobbish and European-leaning. My third source as a geeky kid who liked reading about cars was…Consumer Reports. In one issue, they rate a Toyota Corolla SR5 5-speed over a BMW 318i 5-speed (THAT I did not agree with). CR also raved about the ‘new’ 1977 Caprice.
But the car magazines drove new cars–and not just any new cars, but cars that the manufacturers went over with a fine-toothed comb.
So the Old Diesel–it was brilliant! Engine performance and economy comparable to a Mercedes 300SD for a lot less–and delivered in an excellent interpretation of the American car.
The X-car….May 1979, Car & Driver…. “GM blows the imports into the weeds” or some such headline on the cover.
We know how both those stories ended….
It’s not all bad. The auto press raved about the Rabbit GTI. No big let down here 5 or 10 years later. Or the Honda Accord. Or the 1983 Honda Prelude. Or the Toyota MR2
The 1994 Probe GT…in the middle. Great as a new car, but so-so as an older car. Perhaps because my family had two of them, and we have first-hand experience…not all good.
Now the original Fiero…got middling reviews. “Great looker, mediocre driver”. And it turned out be a mediocre car, until the last year. GM fixed it, then pulled it….
Maybe Paul or some one can do a piece….Deadly Sins of Car Magazines…where the reality differed from the road test review.
You’re missing a key factor: the inability to predict future reliability.
All these cars that you listed generally performed well enough, when new. Their issues happened after some period of time. How should they have known that? They simply reported what they experienced. And if you read this one by R&T, they do raise valid questions as to its future reliability.
Obviously car journalists have an interest in creating excitement about new cars, as they’re car enthusiasts themselves. So the tendency to focus on the new features and qualities of a new car in their initial reporting is natural.
R&T was not really in that league, as these reviews make pretty clear. And they bought and kept cars for 24k miles or longer. Their VW Rabbit long term test, which we reposted here, was a scathing indictment of the early Rabbit’s weaknesses. Too bad they didn’t do a long term test of the Olds diesel.
Good points. Thanks for reply.
Yes, R&T was a little more ‘circumspect’ than C/D.
I also liked R&T’s long-term tests, they seemed pretty honest.
I also liked R&T’s “Technical Correspondence”. I found it often very informative.
I would not be surprised if R&T DID ask for a long-term Olds 350 diesel, but GM said “sorry, we don’t have one to spare…” If they knew about these issues, and I’m 98% certain the senior managers/jr execs who made the decisions subject to the parameters set by the VPs did know, it stands to reason they would not let a car like that in the hands of an honest reporter. Too much risk.
I still think there is an article waiting to be written here…”biggest disconnect between car magazine review and actual experience”. And this deadly sin may well be at the top of the list
Is that one Camaro long term CD review posted here, where they couldn’t even finish the 20k miles due to defects and had to give the car back? That’s possibly the most damning review I’ve ever seen.
CR rated the Corolla over the 318i in the late ’70s, that I can’t imagine in absolute terms but can easily imagine if value-for-money was taken into account. The BMW cost over 50% more but wasn’t half-again as good as the Toyota.
I wish I remembered the details. I don’t think it was the value proposition. The would show up in the summary.
The SR-5 was a hatchback (more versatile), that may have been a factor. Perhaps fuel economy? Perhaps the FIFTH gear? I want to say handling…because in the 318i one could more easily induce oversteer, and that marked down the ’emergency handling’ (the other category, “regular handling”, I’m sure the BMW aced that.
I think the BMW was 2nd or maybe 3RD out of four. Not sure what the other 2 cars were….Mustang II? Scirocco? 200SX? I think it was “Sporty coupes”
It had to be 1977 or 1978. I didn’t even have a learners permit, but I thought, “are these people for real?”
Yes. Also, back then (mid/late 1970s), Consumer Reports treated cars like consumer items. Very little emotion. For example, they recommended avoiding options like power windows and power lucks, because they added relatively little utility, but were prone to breaking and needing repairs.
Their acceleration test data was also more realistic for average drivers. They also reported fuel economy SIX different ways: 195-mile test loop; city; highway; they mixed those three to determine “gallons used in 15,000 miles” (that’s SEVENTH way!); steady state 40, 50, and 60mph. REAL data–I liked that. Later they reported how much it cost to repair a bumper.
Maybe the Honda Accord hatch was in that group, and was number 1, despite it’s slow acceleration.
What was GM trying to achieve here?. It took 100 000 miles to recuperate the extra cost compared to the 260v8 . The engine design life was 100 -125000 miles.. Great so as soon as you got your extra cost back the engine had worn out.time for a new car. I could go out and buy a boat load of MB 123 series, 240 and 300D with 4-5 00000 kms on their original engines!.
Popular on France because the road tax was the same as gas 2400cc engine cars. So just about affordable. Jags cost thousands in comparison.
One thing that set Consumers Report apart from car buff magazines is that they purchased cars from direct from a dealer while a magazine like Motor Trend would receive a car from one of it’s revenue streams/advertisers, which was likely carefully prepared by the manufacturer. Guess that explains the Corvair, Vega, and Citation being Motor Trend’s 1960, 1971, and 1980 Car of the Year.
And C/D, M/T & R&T could have easily purchased cars and done honest reviews on non-ringers…but that would have cut into the profit margins.
If the Olds diesel had been fully baked it would have been a great way to get decent mileage in a large automobile. In an alternate universe it was a robust engine and was also available with a turbo.
The thought of these being sold in Europe just about makes my brain’s head gasket explode. I’d love to know how many were sold, and in what year they became extinct. Maybe by 1985?
In any event, here’s a 1979 French ad for a Delta 88 Diesel:
Here’s an example of such a car—European lights and all.
They were sold there but not in any great numbers. Seeing an American car when I was a wee lad was an extremely rare sight, sort of analagous to spotting a Ferrari or Lamborghini over here in the US in the ’80’s or early ’90’s, i.e. it happened but not daily, weekly, or likely even monthly. Switzerland seems to have a greater percentage (anecdotally speaking) than most other countries though.
Here in Austria this generation GM B bodies – often as station wagons – were a part of the street scene well into the 90s. I have no idea how much were diesels but apparently due to our hp-based taxation system they were not as expensive to run as one would think due to low malaise era power ratings. Very useful if you needed the space to carry people and things around. They are selling around EUR 10K these days – just the thing to carry wood for your oven in…
https://www.willhaben.at/iad/gebrauchtwagen/d/auto/chevrolet-378890000/
In Israel where I grew up these diesels were sold in Checker and Olds cabs and I have no doubt they contributed greatly to Checker’s woes overall – Israel was an important market for Checker and its cabs were as popular as MB’s and Peugeot’s offerings on account of their unburstable construction. Until Checker had the bright idea of fitting those horrible things in its cars they used 4 cylinder Perkins units which were less powerful but lasted for hundreds of thousands of miles. Ultimately there was a class action which both Checker and Olds lost. The importers were ordered to repay owners the cars’ price in full and take them away.
They were left with the unwanted vehicles on their premises ultimately I believe most of them ended at the bottom of the Mediterranean!
Really sad because my understanding is that later GM V8 car & van diesels were reasonably reliable. A 5sp equipped 6.2 Olds would have been viable here in Austria for sure.
Thanks so much for this information, and the link to the wagon for sale – very interesting stuff!
A/C and cruise control still optional on a £7200 car.. Big money for the day.
I remember reading that many years ago but of course we never saw the actual cars except the odd one or two private imports so the disaster they became never really became an issue, if you wanted a diesel car here Peugeot or mercedes would sell you one at horrendous cost or you could grow your own and plenty of people put Fordson tractor engines into old sidevalve Ford pickups there was a kit available to do it and OMG were they slow, 0-60 nope they wouldnt go quite that fast 50mph was about it.
Geez, how many could have sold? Odd how they used an eagle in the advert. That was more of a Buick thing during that period.
The eagle represents America in this case.
Coulda used Travolta in a disco suit at that time, so good they went with the eagle.
I think that GM used the eagle, and the tagline “American Cars by General Motors” (always in English) throughout Europe in the late 1970s.
Good god almighty, how awful all around.
No – we cannot predict future reliability. We can’t even predict how much maintenance a good vehicle receives, which is vital for a diesel. These could have been very good cars, but without the maintenance, they wouldn’t have been reliable.
For me I wonder, how these cars would have evolved had they been allowed to evolve. In a perfect corporation, GM would have given these diesels the time needed. Yet, I am aware that you cannot make a buck on an engine you don’t sell. Who has endless piles of cash for proper development? Very few of us.
Then there is, “in for a penny, in for a pound” issues. You commit for a launch and withdrawing that launch could cost more than launching a half-baked failure. We’ve all see half-baked first year cars that evolve into something incredible. GM is famous for that.
I cringe when I think of these vehicles hitting the Autobahn.
Maybe the Germans just painted them safety orange and used them as road construction barriers.
“Farfrommovin”
“half-baked first year cars that evolve into something incredible. GM is famous for that”
And then cancelling them. The last year a GM car is made is sometimes their most reliable model.
The 5.7 litre diesel is a car that doesn’t get any respect. That’s because it doesn’t deserve any. They marked the beginning of GM heading to crap.
The diesel technically would have been much better with a Bosch injector pump, head studs, a roller cam and a proper water separator. The motors were rushed into production and the consumers (usual) did the testing..
By 1981 the motors were quite reliable but the word was out not to buy one. Savvy folks are going to do that math and see it’s not going to pay for itself for like 200,000 km.
It’s a real shame because GM could have been America’s diesel company.
Such a shame that marketing always drove that eagle. I disagree about the DB2 injection pump. Stanadyne could have done better with a little more time. My dad rode shotgun from Lansing to Colorado Springs with one of the Olds test crews as the rep from Hartford. He was always impressed by the commitment and energy of the Olds staff but couldn’t believe the deadlines they were under. The directive to get it done sooner, make the diesel cackle civilized, keep smoke down, and make it cheaper (thus no water separator) all contributed to the fuel system problems. They sure got great mileage in a comfortable auto.
GM was already heading to crap long before these hit the
roadbreakdown lane. The Vega. The ’71 B-bodies. The TH-200 “transmission”.To be fair, the Delta 88 Royale Brougham was a very nice car. The driver’s seat was better than any other GM B-body. With FE3 these cars were fun to drive and with 240 ft/lbs of torque for the 307 the cars never felt slow. With LPG, a 307 would literally last forever. One million km was possible without any major repair. The earlier 350 gas cars were really nice and made the car fast for the time.
I am so intrigued by these tests of the Olds oil burners. Am I the only one who thinks this barge was actually swift? I can’t wrap my head around 15 seconds, give or take to 60, being real world…
Hey this is 1978. An Olds 260 gas was making similar power.
0-60mph in more than 15 seconds was not that uncommon in the mid-late 20th century. You are thinking from a 2020 perspective. I still remember Toyota proudly advertising “Zero to sixty in sixteen seconds” for the Corona.
I understand the metric itself being strange in today’s world; I honestly meant back then. To me, to only need 14.4 seconds to sixty, in this size car, seems wildly fast, and at odds with the specs. If true, it goes a long way to make me understand the rational appeal one *might have* behind the idea.
The title of the article mentions “Just a smatter of clatter”. The Olds diesel was the worst sounding engine that I’ve ever heard. They were absolutely horrible. My only experience with them was to hear them rattling like the crank bearings weren’t ever installed. The horrid sound would get your attention and when you turned to look at what was making that death rattle noise you would then see that it was a Cadillac Seville, Eldorado, or deVille, or a Buick Electra or Riviera or an Olds 98, 88, Toronado, or Pontiac Bonneville. This was not just a bad engine. It was installed in most of the premium offerings that GM sold. After a few previous engineering disasters that affected only the lower end of the GM product range, this engine let the rich GM customers know that they too could buy Chevy Vega quality at a very premium price. This engine alone might have been the final nail in the Sloan Ladder as many GM diesel owners bailed and bought imports and never looked back.
“With gasoline at 65–70¢ /gal. and obviously heading up…”
65¢ in 1977 is $2.98 today according to an inflation calculator.
And I filled up for $2.49 today
About what we are paying today in California, after a recent major drop.
Were it not for the Olds diesel one of my past customers would not have been quite as successful as he was. He was a one man diesel repair shop, very good at what he did, never lacking business.
One of his regular customers had an Olds diesel that no Olds shop could get to run right. He agreed to take a look at it (as a courtesy) and was able to resolve the problem. His customer told a fellow Olds owner, and so on, and so on. His reputation was so good even GM dealers were sending him diesel business.
For several years his business was very profitable in large part due to Olds diesel. As the diesels died out he converted back to working on class 8 vehicle diesel engines.
He said the Olds diesels were definitely a good ride for the business and was sorry to see them go. When I asked if he would own one were he not a mechanic he gave me a resounding “no way”.
Optimism, then Pitchforks and Torches-The Olds diesel story….
Ah the Olds diesel. Pay more when you buy, Spend more to keep her running. Get less when it’s time to trade. And when I was behind one I’d do anything to get around it, they stunk – particularly when I was on a motorcycle.
My Uncle Jack and Aunt Jayne had one, they in Los Angeles. They having a 2nd home as a get-away on the beach just below Ensenada, Mexico.
Uncle Jack had an auxiliary fuel tank put in the trunk. So when in Mexico, he would fill up both tanks (fuel cheaper to begin with there and no Calif taxes on it.).
A lady in one of our business offices had a diesel Delta 88. She ran into a bunch of issues with the engine. So frustrated with the situation, she attempted to replace it, but no dealer would accept the car as a trade in, not even the dealership which sold her the car.
One of the Deadly Sins that chipped away at GM’s sales base and drove customers to Asian brands.
During a business trip in the early 80’s to Houston, I found an ad in the local paper concerning the GM diesels. For a flat fee, an independent garage would swap out the diesel for a conventional V8. I don’t remember the amount, but I understand his business was very brisk for a year or two.
Just noticed, looks like the first picture was taken at a GMC dealership. Or maybe an Olds/GMC dealer that was also franchised for medium/heavy trucks.
Since you brought it up Bob B…
What do you make of the H-cab’s wide base wheels and fabricated bumber?
Probably set up for a dump or mixer body. Some mixers in those days used a front mounted engine drive P.T.O. for the hydraulic drive pump, which required an extended front bumper. Or maybe a winch?
They were popular in Sweden a couple of years, also as taxis in competition with Mercedes 300D and Volvo diesels. Here is a picture of my survivor
My father-in-law had one and he had a bad experience driving up the interstate a little over 100 miles in a blizzard. The temperatures were low and the fuel line froze up. He had it towed and they put it in the garage and after a while it was fine. I don’t think he kept it long after that.
The flocculation of paraffins at low temperatures is a common problem associated with diesel fuel.
Consequently, in most European countries, it is standard practice during the winter months to blend additives into diesel fuel—while it is still at the refinery—that delay the formation of wax-like paraffin crystals (flocculation). Without these additives, such crystals could clog fuel lines and filters, potentially leading to engine failure. The relevant testing specification for this is known as CFPP (Cold Filter Plugging Point).
Diesel fuel modified through the addition of these additives is generally referred to as “winter diesel.” In Germany, for instance, it is typically available at filling stations from mid-November until early March.
A special blend sold in Scandinavia, designed for particularly low temperatures (down to -40 degrees Celsius), is known as “polar diesel.”
A long time ago: add (premium) gasoline to the diesel fuel to prevent flocculation of paraffins. Up to a ratio of 20% gasoline / 80% diesel.
I was so disappointed by all the problems these Olds diesel V8s exhibited as it was my dream also to continue to drive a big, comfortable and safe rwd V8 US car as we had previously with several full-size Olds, Buicks and Mopars, while willingly suffering the 11-14 mpg inherent with the breed. I’d certainly have bought a several year old 98 Diesel but by then the negative reports were starting to come in, sadly. I’d still take a well proven and well-preserved one.
I purchased a 1978 Delta 88 Royale with the Diesel. I had speced one out, then decided no, we didn’t really need it. I specifically wanted to avoid the vinyl roof due to rust issues. I received a call from the owner of the local Oldsmobile dealer in newport news VA. He said he had a car come in with a mistake on the order, no vinyl roof. It had pretty much what I wanted, except the F41 handling package. It did have the optional wider tires that I wanted. After some haggling he agreed on an $1100 dollar discount off the sticker price (no one was discounting the Diesels at that time). I was able to order the suspension pieces through thier parts department essentially through my business as a comercial customer. There were some issues, car smoked badly, was sluggish and got 10-12 mpg in town, maybe 20 highway. The service techs were still learning about Diesels, so I started researching injection pump timing on the Roosamaster pump. I found where the pump’s TDC #1 cylinder was, but due to the location in the valley between the manifold sides it can’t be reached in place. I made a rubber wedge to hold the pump ring at TDC, then re-installed it, pulled the pump against the drive and marked the adapter with a small cold chisel. Restored everything to normal and test drove the car, light gray exhaust, a bit more pep and after a couple of tanks 25 mpg city, 33 highway. I received a call about two weeks later, a TSB from Oldsmobile regarding improperly timed pumps on some of the early cars, mine was one of them.
I heard a while back, can’t remember where now, that the Olds 350 diesel block was used in NASCAR as a base for the Olds stock car engines. Don’t know if this is true or not, also that Caterpillar cast the block. Just wonderin’ LOL
When I was studying in Hamburg / Germany, in the mid-eighties, there was an Olds 88 Diesel operating as a taxi in town. It was an imposing sight amidst all the W123s and W124s that made up the bulk of the taxi fleet. However, the rattling sound of the engine stood in strange contradiction to the car’s almost stately lines.
I suppose that is what you call cognitive dissonance.
So it’s late ’78/early ’79 and I’m just starting out on my way home after work at Austin-Healey West in San Francisco in my clapped out ’67 MGB (mostly a ghastly orange, with 3-shades of primer at various corners, a ’68 MGB eng/all-sync xmsn, ragged top__I mostly relied on just the tonneau cover__etc., etc., etc.).
Anyway, I’m stopped at the light on 5th St.behind a few cars approaching the Harrison intersection, and for all the world, I think MY ENGINE JUST STARTED COMING APART!
I (panic, of course, and) immediately cut the ignition, but it continues to sound like it’s mechanically exploding!
I start looking around and see that an elderly gentleman had pulled alongside with a brand new Oldsmobile 98 (sticker’s still on the back window); I’m still embarrassed at first, assuming people nearby think I’m the source of this awful clatter.
Once I realized, against all probability, that it’s this brand new luxo-barge next to me, I just BUSTED OUT LAUGHING!
I restarted my car (fortunately, it cooperated) blipped the throttle a couple times bringing it to life; it’s still “cold” remember, and now the light’s changed and we’re moving off.
I never encountered the man or car again on my commute (speculating that he either didn’t keep it, OR MORE LIKELY, it eventually puked its crankshaft & rods out on the pavement like many others did) but I can STILL picture the look of HIS initial embarrassment, turning to disgust when I started laughing. I admit, that was rude, but I couldn’t help it…
I couldn’t keep a straight face, nor stifle some additional laughter*, the rest of the way home to 27th & Dolores, lol!
* No doubt to those that witnessed me, solo in the car laughing, thinking I was HIGH, considering it WAS San Francisco in the 70s…
My Dad’s agriculural equipment sales business had four GM diesels, an Olds 88, two Buick Le Sabre Limiteds and Dad’s Buick Park Avenue. None of them lost a head gasket and were driven well into the 70-80,000 mile range so far as I remember. Solid 24 mpg no matter how fast or loaded up with people or stuff the cars might be. Living in central Iowa, only issue was the cold, we had the PA fight to keep going during a cold stretch with the fuel gumming up, an additive got it back going again. We did throw an injector on it once, but frankly that was the only ‘kinda bad’ engine we had. Even then, only cost about $300 plus to repair. Performance varied a lot, and the 88 was by far the strongest. It also had the heavy duty suspension, startlingly flat and controllable handling for a car of that size.
From 1982 through 1998 our family business operated 12 different GM cars with either the 5.7 V8 or 4.3 V6 diesel engines. All were bought used and all 5 divisions were represented.
In the late 1970s I became “fleet manager” (among several other jobs) for my family’s group of businesses. Previously Uncle Fred had this job (again, among many others) but he had left a few years prior due to a disagreement with my father. The “fleet” consisted of about 50 pieces of cars, trucks – ranging from pickups to 18 wheelers, farm equipment, and off road construction machinery. We had a decently equipped garage and a full time mechanic.
The 1970s had been tough for our business and we had narrowly avoided bankruptcy. Most of the light duty vehicles were worn out and rusted away junk but were still very thirsty. When the second oil crisis hit in 1979 our fuel costs went out of sight. Most of the new and used car dealers in our area were customers of ours, including the Datsun/Nissan dealer. The owner of the dealership had become a good friend and he told me about the fantastic fuel mileage (for that timeframe) the diesel Datsun pickups were getting. I tried one out and was impressed. I finally convinced my very reluctant father to buy it. We carefully tracked it’s fuel usage for several months. My father was so impressed that he bought two more. I then started looking at diesel powered vehicles for our other uses.
My mother had been driving a 1977 Chevy Nova. It was a really good car but it got in a wreck. The insurance company tried to fix it but it would not track straight. About then the Nissan dealer took on the Lincoln-Mercury dealership after the previous dealer went bankrupt. Someone traded in a 1980 diesel Cadillac Fleetwood Brougham on a new Lincoln. It had about 40000 miles on it. So I bought it for my mother to drive. It got great mileage, average 23 in local driving.
We had pretty much all the issues that others described with that car. I made a bunch of mistakes as well, like using the same head bolts over after replacing the head gaskets and putting “Dry Gas” alcohol in the fuel. I read everything I could find about these engines and talked to everyone I could. Over time, by trial and error, I sorta-kinda figured out how to make these last. As the bad reputation of these engines grew the local dealers would automatically call me if they got one in on trade. Several local garages doing diesel to gasoline conversions would give me the diesel engines they pulled. I also bought several rusted out or wrecked cars for parts.
The earlier engines were hopeless. You could not keep them running, no matter how hard you tried. The “DX” block, introduced in 1981, was so much better. It included roller type lifters that eliminated the earlier valve train failures. The later engines also had a fuel line heater that really helped with the fuel gelling issues. Using the proper oil and changing it every 3000 miles was critical. I settled on Shell Rotella 15W40. Fuel issues were greatly reduced by installing a fuel-water separator. We also found a good quality fuel supplier and the injection pump and injector issues went away completely. Proper cooling was critical so I started removing the fan clutches. I also learned that the EGR system would lead to soot and carbon buildup with the resulting ring failure. So I committed a series of Federal crimes by removing and plugging the EGR ports.
My highest mileage 5.7 engine was in the 1981 Olds 98 Regency I drove myself. It had over 100000 on it when I bought it and I put about another 100000 on it. The only issue it had was an injection pump failure at about 160000 miles. The TH200 transmission finally gave out at about 200000 miles. A wagon made more sense for me at that point so I sold the Olds to an employee. He put another transmission in it and drove it for several more years. I don’t know how many miles it had on it when he got rid of it. I replaced it with a high mileage 1980 Caprice wagon that had the engine replaced with a “DX” before I bought it. It lasted several years until the fan clutch failed and took out a head gasket. That is how I learned that lesson. I then replaced it with a 1983 Electra wagon. It had the TH700 overdrive transmission and would give 30 MPG on the highway. It finally rusted out but still ran great.
The last GM diesel car we had was a 1982 Olds 98 coupe. I bought it from my best friend who had bought it new. He kept the interior spotless but the cheap GM paint peeled on the hood and trunk lid. I had it repainted and gave it to my mother to drive. After dad died she moved to a house with a small garage. The Olds barely fit and it made her uneasy. She said she wanted a smaller car so I got her a Cavalier. I had wrecked my pickup so I drove the Olds for a few months until my new 1999 F250 came in. By then the scope of our business had changed. I sold off most of the fleet, including the Olds.
So, all in all, it was an interesting ride. I probably spent way more than I could justify on maintenance for these cars but the fuel savings were impressive. Diesel engines just fascinated me and still do. My wife drives a 2018 Chevy Equinox with a European 1.6 liter four cylinder diesel. Other than the silly DEF system, it has been trouble free. GM finally got it right but only offered that engine for two years.
Thanks for the interesting perspective. It confirms what some others have found, that with the right care and commitment, these could last.
A 5.7L Olds Diesel is the only engine I’ve ever seen that RAN with a crankshaft broken in two pieces–a diagonal split right through a main bearing saddle, (thrust main, I think) so that when one piece turned, the other piece had to turn with it.
Knocked like mad. Loud! I saw this during my summer at a Chevy-Olds dealership in 1980.