This is all false. The pan will seal just fine, the pan gasket and drain plug seals are available like any other MB transmission. How do they expect any repairs to be accomplished if the transmission can't be resealed? i have had several of these apart and no unusual problems with leaks. On a 97, there is still a drain plug on the torque converter, so this can be drained as well. The fluid for this transmission is a little pricey, so realize this. It isn't intended to be changed as a service item, but I can't imagine a dealer "refusing" to do this if you really want it done. There is also a trans filter available so this can be done also. The only thing different about doing this, as it sounds like you know, is the refill procedure, as the dipstick is a shop tool, and the ATF temp must be monitored to ensure the level is correct. Make sure they replace the cap lock also, as the tube cap isn't very secure (could come off) without the locking tab installed, and it is a one-time use lock.