Every time I have had to do a coolant change on my C280, I find the thermostat opening a little too early and the engine running too cold. For example, after 3 years the engine will run at a solid 80C on the highway. New thermostat brings it back up to the 85C to 90C range on the highway. Thermostat is supposed to start to open at 85C-87C.

__________________
Ali Al-Chalabi

2001 CLK55
1999 Dodge Ram 2500 Cummins Diesel
2002 Harley-Davidson Fatboy
Merlin Extralight w/ Campy Record