Which thermostat for OM603 (1987 300D)?

[renaissanceman]

The thermostat is stuck open in my 300D, so I'm looking for a replacement. I need to change the coolant back the the Zerex G-05, so I figured I'd kill two birds with one cooling system drain.

I'm looking at an unnamed parts site, and they have Behr Thermot-Tronik and Stant thermostats, both 80C (which seems to be the OEM temperature).

Are these engines sensitive to thermostat brands, or are either of those options fine?

Thanks!

[bsmuwk]

I've had good success with both in a couple different Mercs, though I do find the Behr to feel of slightly higher quality.

[DieselPaul]

The 60x thermostats have a dimple in the them to clear a ridge cast in the housing.

Many autoparts stores thermostat for the 603 does not have this dimple, and it won't fit.

Only the autozone thermostat had the dimple, but it was a 185* Thermostat and the car always ran warm.

In my 60x experience only the Behr fit right and was the right temperature range.

I'd go with the Behr. Behr is the OEM so you can't really go wrong.

[renaissanceman]

I ordered the Behr. We will see how it fits.