722 trans question... quick and simple
 

When did this trans receive the lockup torque converter with Overdrive?

Thanks :)

The 772.6 was the first with a torque converter lockup clutch.

That would be model year 1997 for most models.

I also have a C280 Sport, '97. Asked dealer if I should follow owners manual and never change the trans fluid? Dealer said don't change fluid. Reason, fluid used in OEM trans somewhat special. Might make sense. After 130K miles I see no reason to change but could be wrong. Question, why does MB say unit is sealed for life, even lacking a dip stick?

Old Topic. Do a search. Most owners service the trans every 100,000 kilometers. Use SDS to set the temp at 80C for the fluid level to be correct and use the MB synthetic fluid. MUST use the MB fluid. A 1997 722.6 without a service or updates is on borrowed time.