The 5.5L M117 uses an 80˚C T-stat. The earlier 5.0L uses 84˚C

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Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]

Good catch. I would still just go with standard. On hot days they will all be fully opened giving max heat transfer anyway.

I think the fan ON setpoint is 110C for this one, so that would be my threshold for beginning to worry.

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Prost!

I’ll look at putting an 80C thermostat in soon. I may have just been overly cautious. I mean, there’s nothing super wrong I’d think since it’ll idle with the a/c on at night when it’s 85 degrees out for over 20 minutes and the needle is just above the 80 mark and just sits there. I did the fan test and shut the car off while watching and it stopped pretty quickly, which you can do solo with the hood up looking through the windshield. Now I gotta figure out why my recirc button red led light does not come on when pressed. It’s always something.