VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Convertible Question

OK Chevrolet gurus out there or those who own or have restored them...

Chevrolet like many manufacturers in the 1940s-1950, used an X brace in their chassis frame for convertible models. But, prior to 1941, did Chevrolet use the X for their convertibles or just simply beefed up the siderails? I ask because I have seen a 1936 without the X and know 1941 used the X so how about between those years? Thanks!

Hi, Eric:


I was just flipping through Standard Catalog of Chevrolet (first edition, which had room for all the great feature articles), and according to an article by Tim Howley on 1935-1942 Chevies (including 1936-38 & 1940-42 convertibles), the 1940-model convertible was the first to have the X-member.

The above is correct. The 1936-38 had no X in the frame. Actually the cars with leaf type springs didn't flex the frame as much as cars with coil springs.
I recall riding in a friends 1938 convertible and it had some cowl shake. The 1940-48's had some shake also but in the 1949-52's had was what I would call excessive cowl shake..

1937 to 1939 Australian "Holden" body roadsters and Tourers where factory fitted with the Large X through frame. Early 1937 roadsters and tourers were originally released for sale without them, but were recalled for re fitting. The under floor battery was positioned on the Firewall in the engine compartment, as the X cut right through that area.
So any of the 1937 - 1939 roadsters and tourers imported to the US from "down-under" should/could have the X member in the frame.

Did the 1937 and 1938 have front leaf springs or knww-action?

The 1934-38 encllosed knee-action units were mounted so far out they caused the frame to twist a lot. Thats why the 1935-1938 Master deluxe models did not have a convertible and they just had the convertible in the leaf spring cars.

Here are production stats for 1936-39 Aussie Chevs.

Gene, The majority of roadsters and tourers where on the standard I beam chassis. But they were also available on the master deluxe chassis . I have a 1938 magazine advertisement that says " Master deluxe models are available with Sedan, coupe , and sports roadster bodies" .
There is a 1938 tourer in Brisbane which is reputed to be an original master deluxe tourer,(one of the Five Listed in the above post), but i don't know the full history, It was owned and restored by the Reproduction casting company owner who was a VVCAA mmember of long standing..

1939 roadsters were only available on the standard chassis, but i was recently given 1939 roadster photos from GMH at woodville which appears to be a of a Master deluxe, but is hard to make out and confirm it.

By the way CarHistorynut,
Thanks for posting the chart on Holden Body production figures. A pity it is missing the 1936 figures. Another point is that it contains 1939 Business roadster production at 116 units. This figure is missing from the History of Holden book, and only quotes the 88 bodies for sports roadsters. I think the recent imported 1939 roadster by Andy (61 vert) is a body number in the 100's.

You're welcome. I've noticed a few differences between this document and Norm Darwin's book, too. I think the Oldsmobile figures are slightly different. Incidentally, 1936 is present. The "6" looks a bit like a "5" but it's definitely a "6". I have 1935 on another page. If you're interested in the whole document (PDF), I'd be happy to email it to you. It has totals from 1917 through 1949, with breakdowns from 1927 through 1943.

I wouldn't exactly call it a true X member but more of a K member while 1941 went to more of a VK type frame - still not a true but more so than the unique 1940 type. Yet, does anyone have a 1940 shop manual that shows the frame diagram? Thanks!

Jack - any manuals that show the frame with dimensions of the years you are speaking of - to get a sense of the frames as well? Thanks!

Gee... can't edit a post.

Here is a 1940 Chevy Convertible (Cabriolet) frame on a hot rod but frame was left original. Can see it is basically a sedan frame with a couple of added on back legs creating basically a K rather than a X since there is no central axis.



Anyone with the shop manual diagram?

You can edit a post for up to 1 hour after making it.
I dont have any plans with dimensions. The X is made up from 4 vertical plates , which then have a top and bottom plate fillet welded to it. It is flush with the top of the chassis rails , but the lower side steps down about an inch lower than the chassis side rails. The top and bottom plates extend over the upper and lower chassis rails , and is welded at those points.

It is a lot cruder than the chassis which you have shown,with pressed frames and the rivets, but it did work. GM-H were not building complete chassis, they were assembling them from crates and then fitting thier own bodies to them around Australia at assembly plants.

For anyone interested, I did run across a frame chart of sorts for the 1940 Chevrolet Convertible. It is a body shim chart from the July, 1940 "Chevrolet Service Topics" shop bulletins (Vol 2, #12). Not a very clear scan but gives me some idea. Does anyone have an original copy of this bulletin so I can get a cleaner scan of it?

Here is the online one:



Link:

http://chevy.oldcarmanualproject.com/bulletins/cst/images/40cst0703.jpg

Thanks.

Hello: If I change the picture on my desk top from 100% to 200%, I can read everything on your scan. Many VCCA members have had good luck by contacting the Tech Advisor for a particular year. The 1940 Chevy VCCA Tech Advisor has a great 40 convertible. His name and address and phone number is listed in the G&D.

dtm

The scanned chart I found and posted is a bit rough even enlarging it - dropped lines and scan zig-zag edging. Looking for a cleaner scan. Will try your suggestion but what is the G&D? Thanks.

The G&D is the Generator and Distributor, monthly magazine for the Vintage Chevrolet Club of America. It is sent to current members of the VCCA. If you are not a member then we suggest you join to enjoy all the benefits of membership. Access to Technical Advisors is just one of many.

I see that you are not a member of the Vintage Chevrolet club of America. When you join our club you have many advantages. For example you will receive the Generator and Distributor, our monthly magazine. This publication has many interesting articles in color and a section for free ads to purchase or sell parts. You will also have access to the Technical Advisor for you year vehicle. This will open up areas on this site you can't access as a non member. If you need help joining you can contact me for help.

Ray, I would be glad to join "if" I owned a vintage Chevrolet. If I did it would be a late 40s-early 50s fastback style. Always loved them. But my project i am working on is a paper project for many makes of automobiles. Wouldn't benefit me other than seeking out that one page scan from a shop manual or this service bulletin.

Eric

Body # 113 to be exact.Would that make it the 4th from last business roadster made?

Hi 61 vert,
Yes , that would be the the 4th last one built if the figures are accurate. the reason i say that is there is a master deluxe sloper here that is number 54 out of 53 built according to the records.

Thanks for the info. I am taking the 39 apart for paint and have discovered that the passenger side outside door handle is broken. Any chance of finding one over there for me? I will post in parts wanted also.

Hi Andy, I have sent you a PM with a possible source for another handle (NOS). If he can't help i will find one for you. They are a diecasting and do give the usual problems, pitting with age, cheers Jack

Bumping this back up...

Anyone with the 1940 Shop Manual or aftermarket copy on CD that can post a scan of the frame page - hopefully with the convertible frame? Thanks!