Is it fair to say that the Transmission is failing after 80K miles?

Yes. Talk to your friends. I do not have a single friend who has had a problem free german car. The cars are engineered with complex designs which appear to have problems over longer periods of time.

Mine asnt failed on me yet but it does shift a little harder than it used to.

mine shifts kind of hard from first going into second, but other than that i haven't had any problems as far as the tranny.

No thats not normal.

you need to warm car before start to drive because germans did make feture that you can race car right the way... then will start shift normal and smuth

Find a good independant mercedes shop in your area that you can trust. Have them scan the computer and give you the codes. Have them sit down and explain them to you. Let me back up a bit. Tell them that all you want is the codes scanned, nothing else. Mercedes transmissions have their own codes, and you need the Mercedes Benz program to read those codes. 9 times out of 10, the transmission is reacting to a problem caused by another problem somewhere else. Its more of a symptom more than an illness. I, myself, have a bad Mass Airflow Sensor, and its causing slow hard shifts, and no power when cold. I've seen Mercedes transmissions go 300,000 miles with proper maintenance. If no transmission code show up, its probably something else. if nothing shows up, your's probably needs serviced. Fluid and filter change.

A careless driver can kill a trany in a lot less than 80k miles.Drivers need to understand that the bands inside the transmission were not meant to be used as brake pads.Brake pads are essily accessable and inexpensive to replace,transmission bands are not.People who throw their car into park before the car is COMPLETELY stopped are abusing the tranny. People who go out of reverse by putting the car into drive before a COMPLETE stop and before the momentum shift of the cars wieght settles are grinding down their trans. bands in the most abusive and ignorant way possible.If your transmission goes out at 80k look in the mirror for the reason it failed.And do not forget transmissiopn fluids need periodic replacement just like the oil in your engine.

If possible find out how often (if ever) the transmission fluid and filter have been changed. MB schedule is to be done every 39,000 miles. VERY few people actually do this. Because on most American made cars - you do not need to do this until 100k miles. Local MB dealer will probably tell you that almost always - if a customer comes in with a transmission issue it is usually due to never being serviced.

Wow, only took 5 years for the poor guy to get an actual probable cause answer that anyone worth their salt would agree with. Well done bobkat, give your self a pat on the back!

Thanks Mick, have a good day