I have been servicing a customers 1997 e-320 (104 motor), for six years now.
When I started, he had 155,000 miles.
Just last week it rolled over 375,000 miles and it runs, looks and drives like new.
I replaced the front shock absorbers rcently.

he did need a transmission overhaul at 275,000 miles, but the motor never had a head gasket or valve job done yet.

I resealed the upper front timing cover and replaced the water pump around 300-k miles.

All highway miles in the southeastern region of the U.S.

He wants to get rid of it, bacause of maintenance costs, but I'm as inexpensive as they get and I come to him for the maintenance.

He is looking at Lexus's.-not a bad choice, but the benz runs and looks so good, but he is worried that something big is going to go.

Oh, I had to do an emergency alternator repair for him also a month ago.
I drove 150 miles to get him going( how's that for service).
He was in the middle of nowhere in Tennessee on some back road, and he was petrified to let any of the locals look at his car.