^ Not new to cars, but Benz newb ^

I've got a 1981 300D (NA) that's in need of a new transmission (no reverse, can't be adjusted anymore).

I've done a fair amount of research on it:
How to decode trans numbers
List of Years/Models/Trans Codes
...and quite a few threads here

I converted the trans code page into a much easier table/database format so I can create a list of cars I can get a trans from... but it seems that the number of exact matches with my car is very small... given I've got a 722.118 / W4A020 the only exact match would be a 81 300CD, and I'm not seeing an overabundance of those around.

And thus, I'm deferring to the knowledge of the forum. There are a lot of threads on swapping to a manual tranny... and a few specific threads on "I got x motor into y car", but I don't have enough general diesel benz knowledge yet to extrapolate from there.

My question is, how much can I really tell from the trans numbers? Will anything with a 722.1xx bolt on to my 300D/722.118? Will a .2xx or .3xx bolt on? Does the W4A020 mean anything?

I'd really prefer the least amount of hassle (pressure converters, hacks, modifications, sacrifices to some obscure transmission god, etc)




And then there's always the money question... if I were to have a good turbo motor and tranny from an 84 300SD (____/722.303)... could I swap that in? Say from a total'd car? Without welding?

As always, thanks in advance for any insight.

According to the Hollander cataloge, that tranny should work in your car.

This is a great question. Does anyone know the answer?

If I'm not mistaken one of the main problems with finding a transmission that will work with these cars is the shifting mechanics. I believe that there weren't many models that used a combination of just vacuum and a kick-down switch without the kick-down cable like the 80-81 300d's do. I have an 81 myself and was worried when the transmission died a few years ago. The solution wound up being an 84 240d transmission. It had a kick-down cable so we had to rig a way to attach it to the throttle but it has made a tremendous difference in drivability compared to the old transmission. As far as I know any of the transmissions that will bolt to the engine will work except for the turbo 300d transmissions which from what I hear are geared differently. Sorry I don't know exact years but I would assume at least 79-85 240D's and of course the 80-81 300D's will work. I think that some of the earlier 300D transmissions may work but I really don't know much about them.

I think that changing both the engine and transmission from a turbo 300d to your car will work without welds. From the junk turbos I have access to there are no visible difference in the mount points and I believe the chassis is identical between the two type of engines. I believe the only difference is the rear end gear ratio which on the non-turbo's is a bit lower.