I am in the process of rebuilding the automatic transmission that came with our 1979 Mercedes 300SD. The front pump ate the torque converter. Right now there is a good used unit running around in the car. Is it a good idea to reinstall a rebuilt automatic transmission with a used torque converter?

Depends on your risk tolerance. If the torque converter blows up, you're in for another transmission rebuild. The chances of this depend on how hard the converter was run in the past.

Although I have no MB specific knowledge, I have had training courses and experience with trans rebuilds. One of the things I was taught was that after a rebuild you always use a new converter, whether the old one worked or not, as it acts as a centrifuge and can collect contaminants and debris, which with a combination of changes in pressure from reconditioned pump seals and fresh fluid detergents can now become loosened and pumped back in the trans. If you lost a front pump "ate" as you put it, most likely there was metal debris scattered into and around the converter, and I would not risk pumping that back into my new trans.

I couldn't put that one back in if I wanted to. The front pump literally ate the converter.

Thanks for the posts.

the tranny manual says that you can resuse the torque converter
if there is not metal particles in the pan... if there were metal particalse
then it needs to be renewed.

All I can say is I did it on my 80 300SD (same problem) and a used one has worked fine for about 4000 miles. That reminds me though, I should drop the pan and change the filter as there is likely to be some metal I couldn't find. If you are completely rebuilding the tranny (clutches, bands, seals), I would say go for it -get a new one. In my case , I just "repaired" one with 125K miles on it, so I took my chances...


Rick

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