VCCA Home Forums TECHNICAL - GENERAL Mechanical - Engine, Trans, etc Identifying 216 Transmission Type/Year and What to Do

Hello folks!

I am in the process of keeping my 1941 Chevy Master Deluxe in as original shape as possible. Currently my focus is on the transmission - I think it has quite a bit of wear as the synchro when shifting from 3rd to 2nd doesn't seem to work terribly well. It grinds unless I double-clutch. Oddly enough the vacuum-assist shift is working well, though ultimately I chose to disconnect it.

So, I am faced with the decision to either restore/rebuild the existing transmission or else install one of the two other transmissions I have which I believe are the 216 variety.

Here's the issue: I seem to recall finding a website which talked about the various years the 216 transmission was made and that there were some fairly significant differences in performance/reliability. Unfortunately it's been several years since I found that website and I cannot find it any longer. Can anyone point me there?

Finally, the extra two transmissions that I do have show some serial numbers. They are "691193 GM20" and "891199 GM12 J2". The latter of these two also has the vacuum-shift module attached. I'm wondering if there is a way to decode these serials to determine the model year? I seem to recall the above website I mentioned allowed you to do that too.

Thanks for any help that you can provide!

By no means am I am expert at the detail level of these 3 speed transmissions. Wha to do know is that there is a tremendous amount of commonality and interchangeability over a wide range of years.

I would not be surprised if you could use the synchronizers from either of your extra transmissions in your original.

. If you look at web page <http://home.znet.com/c1937/RPM.htm> it notes that 1937 - 69 transmissions used same parts with these exceptions: The 1937 - 39 passenger is 9" long and uses spur gear for Low & reverse.. The commercial used same trans with longer tail shaft so it was 12" long and could be interchanged with 1931 - 46 4 speed. The One ton, Police and Taxi had bearings in counter shaft instead of bushings. The 1940 used helical low & reverse gear and case was slightly longer with side shifter instead top shift. The 1953 used bearings on all counter shafts and was 14" long. And borrowing appropriate parts, Corvair 3 speed gears will fit in a 37 case. The 1954 "Heavy Duty" 3 speed is completely different. .
. I do not know of a 216 transmission web page. You might try <https://www.jalopyjournal.com/forum/threads/what-trannys-fit-216-engines.284257/>, <https://shop.bowlertransmissions.co...t-6-to-small-block-bellhousing-automatic>, <https://paulsroom.com/BlueHost/web%20files/ChevyEngineSwap.html>, <https://www.hotrodders.com/threads/transmission-1947-chev-half-ton.544595/>, You might see if they have parts for your transmission. .

The vacumm asist was very hard on the sync. dum. It over worked the sncro when shifting. very common problem on cars with vacum shift.
That 3 speed transmission design ran from 1937-1965 with many changes. The syncre. dum was the same from 1940-early 1953, The casting numbers posted are not in the book but are possiby fr0m the mid 1940s and perhaps yu could ind a good syncr. drum from thee pair.
Double clutching or a slow shift can also eleminate the probem.

I just put scyro’s in the trans in my 47, it was grinding in second and third gear. All it needed was the scyro rings, and gaskets. The filling station had the parts when I did it last fall.