Going anything over 90 (anything over 4,000 rpms), the transmission is smoking. I can't tell while driving, I could only tell when stopped and smoke would come from above the manifold (?) where the trans is.
I am going in for a trans change today at the dealership in Tucson just to be safe.
But keep in mind, the temp of desert on the drive out here to AZ was 104 most of the way, and with the AC on, temp was always between 90 and 103 or so. About 500 miles of this.
Kept it under 90 once I noticed the problem though.
2006 E350 w/ 155k miles (Daily Driver)
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)