Automotive History: General Motors 1949-50 – The Mystery Of The Missing B Body (Part 2)

In Part 1 (here), we looked at the way in which General Motors converted its A, B and C body shells from the old pre-war styles to new post-war designs.  Well, the A and C bodies at least.  We established that there really was no B body car produced for 1949, unless we count the handful of warmed over ’48 Buick Specials (that were called ’49s) before Buick pulled the plug on them in December of 1948.  1950 would be different.  Or would it?

1950  A New Look For The Big Cars

The 1950 A body cars, from top to bottom: Chevrolet Styleline, Pontiac Chieftain, Oldsmobile 88


The A body situation was unchanged for 1950.  All Chevrolets, all Pontiacs and the Oldsmobile 76/88 made up the choices under the “A” column.  This made sense as those cars had all been brand new the previous year.

But when we come to the B and C body situation of 1950-51, another mystery presents itself because the lineup was quite unlike anything from GM’s recent or subsequent history.  Was the 1950 model a year of new B and C body cars in the normal progression of GM’s postwar plans?  Or was the new 1950 body an emergency makeover of the C body with some temporary alterations made to cobble up a B body so that Buick would have some Specials to sell?  Let’s look at the evidence.

The 1950 “B body” Buick Special Jetback sedans


The very first of these new models was the 1950 (or late 1949, if you prefer) Buick Special.  Introduced on August 8th of 1949 (and in fastback “Jetback” versions only), the Special would be the first clue to a bold new direction in GM styling that was quite different from that of the new designs of 1948-49.

The 1950 “B body” cars, from top to bottom: Oldsmobile 98 DeLuxe Sedan, Buick Model 41D Special Tourback, Buick Model 51 Super Tourback, Buick Model 71 Roadmaster Tourback, Cadillac 61


As we discussed last time, the Buick Special Tourback sedan and all the rest of the 1950 Buick models came along in due time, as did the Olds 98 and Cadillac 61, and all on a brand new body.  We will get into the name for this body shortly (note the use of quotation marks when identifying the B body in captions to the pictures), but let us at least look at the variety of sedans that shared this new 1950 structure, whether called B or something else.  The defining feature of this sedan body was the vertical C pillar and four window greenhouse, which was quite unlike any other roofline offered under the GM umbrella.

What is unusual is that the Buick Special and the Buick Roadmaster shared the same body.  At least one version of the Roadmaster.  Also notable is that the Cadillac 61 got demoted to a lower level body than the Cadillac 62 this year, a first for this split since 1947.

Popular Science Magazine took a first look at the new Buick Special in its September, 1949 issue and called it “the biggest ‘big little’ car they [Buick] have ever produced.”  Particularly odd was that the Special’s 121.5 inch wheelbase identical to that of the more expensive Super, with which it shared this body.  The wheelbases of the other cars on this body were 122 inches (Oldsmobile and Cadillac) and 126 5/16 (Roadmaster).  The Special was also within fractions of an inch of width of the larger cars, 79 13/32 inches vs. the bigger cars’ 80 inch widths.

And just a word about the nearly 80 inch width on that 1950 Buick Special:  Those were wide cars.  The ’50 Lincoln Cosmopolitan measured 79 inches in width and the Packard Super Eight was only 77 inches.  A ’50 Chrysler New Yorker was a touch over 75 inches across.  In fact, even the 1957 Chrysler New Yorker was  only 78.8 inches wide (all figures according to the

The 1950 C body cars, from top to bottom: Buick Model 52 Super 126, Buick Model 72 Roadmaster 130, Cadillac 62


The big C body Buicks and Cadillacs were noticeably new this year as well on a brand new structure that was unequivocally a C body.  It is interesting that the Buick Super 126 employed a wheelbase of 126 inches, as long as that of the Cadillac 62 while the Roadmaster 130 carried a wheelbase of 130.25 inches.  You can see that 1950 brought two variations on the new body.  It also brought us two versions of the Buick Super and two versions of the Buick Roadmaster, with the “normal” versions that shared a roof with the Special and the plus-size longer wheelbase versions that used the Cadillac roof.

The six-window body was unquestionably a C body.  But was the four-window body a B body?  Or was it a C body that got some minor modifications to temporarily fill a gaping hole in the Fisher Body lineup?  No matter how we resolve the body nomenclature, we have an anomaly in 1950: Buick either built a C body Buick Special or it built a B Body Buick Super and Roadmaster.  Either choice was a big departure from both Buick’s tradition and from the way the Buick lineup would progress into the future.

1951   Will The Real B Body Please Stand Up

All of this quibbling over whether there was a 1950 B body makes no sense until we look at 1951.  Because in 1951 one more body joined the party.

The 1951 A body cars, from top to bottom: Chevrolet Styleline DeLuxe, Pontiac Chieftain DeLuxe, Oldsmobile 88 DeLuxe


Once again the A body cars remained unchanged other than in some styling detail and the discontinuance of the Olds 76.  This would be the last year of the A body Oldsmobile 88 line, which had been pared down to only two and four door sedans.  Some sources indicate that the A body 88 did not make it all the way through the 1951 model year.

The 1951 OB body cars, from top to bottom: Buick Special, Oldsmobile Super 88


In January of 1951 a new body joined the array.  Sources indicate that GM called this the OB Body and it included the 1951 Oldsmobile Super 88 and the 1951 Buick Special.  This body is interesting because it transitioned the Olds 88 out of the small A body and into a larger car.  Although it really wasn’t a larger car in that its wheelbase was either the same 119.5 inches on the new OB body as it had been on the A body or a whopping 1/2 inch increase to 120 inches, depending on which source you want to believe.  It should also be noted that both the A body 88 and the OB body Super 88 show identical figures for width:  75 3/16 inches.  The new one at least packed on an extra hundred pounds or so and was styled in line with GM’s then-current direction instead of the 1948-49 look that GM styling had abandoned.

This new body was also notable for providing the basis for the second completely new body for the Buick Special in as many years.  It was substantially narrower than the 1950 model at 76 11/16 inches (down from fractionally under 80 inches), but still retained the 121.5 inch wheelbase from the otherwise larger 1950 version.

As tempting as it might be to say that the 1951 OB body was the new version of the B body, this would not really be accurate as the old contender for the B body name remained in three different showrooms.  That vertical C pillar is the giveaway in both the Olds 98 and in the Cadillac 61, so if these cars had been built on the four window B body in 1950, a B body it likely still was in 1951.  Buick’s use of this body was a bit mysterious.  The Model 51 Super sedan was relatively unpopular, being outsold by the C body Super roughly 9:1.  This is somewhat odd, given how broadly the body had been offered by Buick in 1950.

The larger mystery is the Buick Custom Special sedan (Model 42).  This model shows up in a brochure, as shown above.  However, according to production figures at no Model 42 sedans were actually built.

The 1951 C body cars, from top to bottom: Buick Super, Buick Roadmaster, Cadillac 62


The genuine C body cars were back too, and largely unchanged.  One difference was that this year the Buick Super and Buick Roadmaster would each come in a single flavor and on a single body instead of the double helpings of each that dealers had seen in 1950.

1952  GM Starts Returning To Normal

The 1952 A body cars, from top to bottom: Chevrolet Styleline DeLuxe, Pontiac Chieftain DeLuxe


It is immediately apparent that things were simplified to a considerable degree by 1952, which displayed a sense of the normal which had been absent from GM’s offerings for several years.  The A body was used by just two Divisions in 1952, Chevrolet and Pontiac.  Also this would be the final year of the fastback versions of A body sedans, cars which have been outside of the scope of this examination.

The 1952 OB body cars, from top to bottom: 1952 Oldsmobile DeLuxe 88, Buick Special


The OB body was the last B body standing, as what had passed for a B body in 1950-51 was now gone across the board.  One question which will go unanswered in this series is whether the OB body served as a basis for the new 1953 Chevrolet and Pontiac A body.  The ’53 Chevrolet’s increase in width over the ’52 (from 73 15/16 inches to 75 inches) to the ballpark of the other OB cars makes one wonder.

The 1952 Extended OB body: Oldsmobile 98


The one new vehicle this year would be the 1952 Oldsmobile 98 which was now built on a lengthened version of the OB body from 1951.  Oldsmobile’s move to the OB structure would have left the Cadillac 61 all alone on the old body, but Cadillac discontinued the 61 series for 1952.  It is not controversial to state that the Buick Roadmaster had made the Cadillac 61 largely superfluous in the GM hierarchy.  From this point forward all confusion about what was or was not built with the B body had vanished.  The Oldsmobile 98 went on a bit of a diet, dropping from the 80-inch-wide 1950-51 “C minus” body to 75 21/32 inches with the OB architecture (a B plus body?).  As a consolation, its wheelbase increased from 1951’s 122 inches to 124 inches this year.  It would appear that a significant amount of the 98’s increase in length came in the rear passenger area

The 1952 C body cars, from top to bottom: Buick Super, Buick Roadmaster, Cadillac 62


Finally the big C body cars continued the new normal which they had settled into the previous year, becoming the lone users of any form of the 1950 body, now in its third year of use.  The Buick Super, Roadmaster and Cadillac 62  would be the sole users of the big C series body for the next several years.  These Buicks measured 80 inches in width, a figure identical to the “B body” Buick Super and Roadmaster of 1950-51 (and within a fraction of an inch of the 1950 Special).

Analysis: To B Or Not To B

All of this confusion calls for a little examination and analysis so that we can make some sense out of this game of musical bodies that General Motors had been playing in this period.

1950 Buick Special Tourback on the “B body” (top), 1951 Buick Special on the OB body (bottom)


First, there is no doubt that the ’51 Buick Special was on an entirely different body than the 1950 model (which had been an entirely different body from the ’48/early ’49).  The February 1951 issue of Buick Magazine referred to “An entirely new, lighter, smaller Special series.”  And Wilbur Shaw tested the new ’51 Special in Popular Science Magazine’s March issue, noting that it was nearly three inches narrower than last year’s car, although it retained the 121.5 inch wheelbase of the prior version.  So which one of these is the “real” B body?

Numerous sources call the 1950 four window body (with the vertical C pillar) a B body, with the 1951 Special/Super 88 being the OB body.  Could that stand for “Other B” body?  Which reminds me of the second Bob Newhart show with the three local bumpkins who were always introduced as “Hi, I’m Larry.  This is my brother Darryl.  And this is my other brother Darryl.”  So perhaps GM had a B body and another B body?  Or maybe it stood for “Oldsmobile B body” because that Division would be the biggest OB customer until the new B and C bodies came along for 1954.

Top: Rendering done by Ned Nickles or R.H. Wieland. Photo source: Hemmings Daily. Bottom: One of two running prototypes of the 1946 Cadillac Interceptor. Screen shot of film. Film source: Mac’s Motor City Garage.


According to an article on the 1950-52 Buick and another on the 1948-49 Oldsmobile at, the 1948 C body had originally been planned as a B body, but was re-named for the more expensive cars well after the planning and engineering process had gotten underway.  That 1948-49 C body design had been controversial among GM management, some of whom found the graceful aircraft- inspired design lacking in the kind of visual heft that its high-end cars should have.  Harlow Curtice was apparently one of those people and, as one moving up in GM management at that time, was in a position to influence styling.  This sketch for an alternative direction for the 1948 Cadillac (along with the Cadillac Interceptor prototype) is quite predictive of the direction the stylists actually went for the 1950 models, including the distinctive 1950-51 “B body” roof and the partially covered front wheels.

This backstory leads to a question:  With a new C body in 1948 and a new A body in 1949, the B body was likely due for an update for 1950.  But did we actually see a new B body that year?  Or was what has been called the 1950 B body actually a second emergency C body reboot (as had happened with the ’48 model) with a shortened variation to fill the gaping hole left by the still-unreplaced B body?  I am tempted to call the two versions of that 1950 structure the C body and the C Minus body.

1950 Cadillac 61 (top) and Cadillac 62 (bottom). Do these cars exhibit a B body and a C body? Or two versions of a C body?


Most sources say that there was both a new B and C body in 1950, with the main difference being in the roof structures.  One example would be the Standard Catalog of Cadillac by John Gunnel, who states that the 1950 Cadillac Series 61 was on a new B body.  He does not, however, explicitly examine the question head-on. Also, Richard Howard Stout wrote an article in the March-April 1977 issue of Special-Interest Autos called Body Politics, which extolled the genius of the interchangeability of panels between the B C and D bodies of 1951.  His analysis, however, which assumes a common 1950-51 B body completely ignores the 1951 OB body which would become the undisputed B body in 1952 and remain so until new B and C bodies would be introduced for 1954.

Thomas E. Bonsall has looked a little closer in The Cadillac Story: The Postwar Years and in Disaster In Dearborn: The Story Of The Edsel.   In both books Bonsall has identified the four-window body as the B body and the six-window version as the C body, although he states that the C version of the body was a relatively simple stretch of the B body with a pair of extra quarter windows to fill the gap.

In The Cadillac Story, Bonsall gives some credence to the theory that the 1950 B/C body program was a crash program that was triggered by the boldly shaped 1948-49 cars coming from Hudson, Packard and Lincoln-Mercury.  The 1948 C body styling had been a product of the Cadillac studio and had been the continuation of a design language that went back to Bill Mitchell’s 1938 Cadillac Sixty Special.  Some in management felt that the 1948 design had missed the new trend towards a bolder, heavier look and lobbied for the weightier styling that came out for 1950, a look which was more derivative of Harley Earl’s 1938 Buick Y Job.  Knowing that in Harlow Curtice Buick had some powerful juice on the 14th Floor of the GM building, it is not hard to imagine Buick getting what Buick wanted.

Bonsall’s look at the issue, however, was from a Cadillac-centric point of view and did not discuss why this new alleged B body had one of the shortest shelf-lives of anything ever built by GM.  It is clear that the OB program had been given the green light well before the 1950 B/C program was even finished.  In any event it would appear that the C body cars were driving the decisions on that 1950 body and that what was called a B body in 1950 was an unsatisfying stopgap, a view born out in how quickly that body dried up and blew away.

The 1950 Oldsmobile 98 four door Town Sedan which, along with the Jetback version in each of the 1950 Buick lines, failed to make it beyond a single year of production.


Bonsall’s Edsel book provided a look at GM’s body system through a different lens.  In the chapter Learning Their A-B-Cs, Bonsall relates the experience of Richard Stout who had spent some time in GM design before moving to Ford.  He had attempted to school Ford on the workings of the GM body-sharing program.  He is reported to have told of the existence of a program within GM to whittle each Division down to a single body for 1949-50.  This version of events, however, again completely ignores the OB structure that was coming down the pike even before the 1950 cars were in showrooms.  Also ignored is the wild proliferation of bodies at this time.  Not only were there A, B, OB C, C Special and D bodies in 1951, but within many of those series were highly specialized versions including two and four door fastbacks, coupes, hardtops, convertibles and station wagons.  GM’s proliferation of models of the 1960’s was not a new thing.

One final data point comes from the June 1951 issue of Popular Mechanics Magazine.  In its Detroit Listening Post column, it was claimed that Fisher Body Division was struggling to meet demand for multiple bodies across multiple lines and was behind a push to cull styles.  The B/C body fastback sedans were to be the first place to cut, proving to be another in a growing string of Bodies By Fisher that were one and two-year wonders.

So what has been the point of this long, long X-Ray look at the General Motors bodies of 1946-52?  We can see that the view close to the ground is not as clean as the “A, B and C body” theory as viewed from thirty thousand feet.  GM was last to market with a fully new line of postwar cars and getting there involved multiple crash programs and U turns in product planning.  The GM juggernaut of the early postwar period looks a bit more messy from up close, exhibiting significant confusion about what their cars were going to look like and how they were going to be built.  What may be the most interesting thing of all is how this story has been told so seldom and and is so little known when compared to the equally tumultuous period leading to the 1959 models.  History is messy business in general, and was particularly messy at General Motors after the war.

If you are looking for a neat conclusion to this tale, I will offer you mine.  When Buick and Cadillac people hijacked the 1948 B body program to make it a C body, this left the real C body program in place and on pace for 1950.  But the problem was that this plan still left a hole where the B body was supposed to be.  The only difference in 1950 was that Buick was not going to stand for being left for another year without a Special to sell.  The 1950 body came in multiple wheelbases (as GM bodies always had) but also shared width and virtually all sheetmetal save the roof/greenhouse areas between the longer and shorter versions.  My conclusion is that what people have called a B body in 1950 was really a C body with enough of a face-saving name change so that Buick could build a Special with it.  The mess that was the 1950 B/C body program (along with the Korean conflict) likely put the “real” B body program behind.  But it finally showed up in 1951 and the “C Minus” body of 1950-51 quietly went away after only two years.

From top: 1954 C body Buick Roadmaster, 1954 Extended B body Oldsmobile 98


By 1954-55 GM would be back to a more traditional A-B-C body system, with some real distinction between the dimensions of each.  This would be especially true in width with the 1955-57 A body being slightly under 74 inches wide and the 1954-56 B and C body cars measuring a bit over 78 and a bit under 80 inches, respectively.  These newer cars showed some real variations in width that were not really seen in this 1949-52 period in which the middle bodies were quite close with either the A or the C in dimensions rather than a legitimate middle ground.

We are all familiar with the story of how the 1949 Ford was a crash program started because management felt that the proposed design was too large and heavy for a Ford.  The proposed Ford became a Mercury, the proposed Mercury became a Lincoln and the proposed Lincoln became the Lincoln Cosmopolitan.  The Ford example is also a display of how this works when the decisions are made in time to make adjustments before plans are too far along.  GM of 1946-52 shows how this same dilemma looks when the decisions were made too late or when there is enough of a budget that it doesn’t matter.  The difference between GM and any other auto manufacturer at the time was that only GM could afford to change body designs nearly as frequently as hotel maids change bedsheets.  Not every problem can be solved with enough money.  But in automobile manufacturing most of them usually can be.

One final point should be made, and it is this.  It is to General Motors’ credit that as much turmoil as there was in its product planning, body engineering and design departments during this time period, its manufacturing and retailing operations were virtually unaffected.  Not just any automaker could have pulled off so many whipsaw changes in its car bodies while maintaining the kind of quality that buyers had come to expect in their GM cars.  And not just any group of stylists could have hidden so cleverly the rapid, multiple body changes that were going on in that period.

Now that we have concluded this tale, you are hopefully in better command of a really obscure period in General Motors’ larger car lines – a period which involves as much grossly wrong online information as I have come across in quite some time.  GM may have been the last car maker to accomplish a full model change after the war, but it was the first to manage two (three for the Olds 98) full postwar model changes in its Olds/Buick/Cadillac lines by 1952.  And the most interesting part is that so many of us never noticed.


All brochure pictures are from the fabulous collection at

Further reading:

1949-50 – The Mystery Of The Missing B Body, Part 1 (J P Cavanaugh)

1950 Buick Special Sedanet: The Full Sized Fastback Problem (Paul Niedermeyer)

1952 Buick Super – Hmmm, Decisions, Decisions (J P Cavanaugh)

1950 Cadillac 61 Coupe – The Ultimate Curbside Classic (Paul Niedermeyer)

1952 Chevrolet Styleline DeLuxe – The Sun Sets On GM’s New Postwar Design (Paul Niedermeyer)

1951 Oldsmobile Super 88 – Rocketing Back In Time (Paul Niedermeyer)

1950 Pontiac Chieftain Eight Deluxe – A Spark In The Night (Jason Shafer)