1997 E420 Transmission
 

This car has 78k miles, and the transmission works well most of the time, except at 50-75% throttle, when the 1-2 shift isn't quite right - it usually feels like it slips for just a split second, then goes into gear fine, and shifts through the rest of the gears fine. It doesn't happen at full throttle, nor does it happen at below roughly half throttle. Any ideas? How reliable is this tranmission generally, and what have the trouble areas been?

Also wanted to get opinions on downshifting this car. Has anyone ever run into trouble doing this with these cars (obviously, without over-revving the engine)? What are your thoughts - less brake wear/cleaner rims vs the (small) possibility of (expensive) transmission damage?

Thanks guys.

I do not have the answer to your first question, but I personally would never use downshifting to slow the car down with a automatic transmission.

When you consistently downshift you are pretty much doubling the wear on the transmission clutch packs by using them twice as much. Brakes are much cheaper than the transmission. No matter how well-built a transmission is, its life will be shortened by consistently using downshifting to slow the car down. The only time I would ever downshift is when going down a long, steep grade, otherwise use the brakes.