35D not getting up to temp

[Z06Luke]

Hey everybody, I bought my 2010 35d about 3 months ago and I've been very pleased with it so far. Today I started experimenting with the hidden menu and decided to monitor coolant temp on my way home from work which is about a 30 mile drive. The outside air wasn't terribly cold at 42 degrees Fahrenheit. My entire drive home the coolant temp sat right in the mid-sixties Celsius. I saw it break 70 one time after a hard acceleration up a Long Hill, and while coasting downhill it would drop into the fifties.

The entire 30 mile trip never resulted in a coolant temp that even reached 160* F. Do I possibly need to replace my thermostat?

[Entropy]

Yep. Bad thermostat. Happened to my 4.8 at 80k miles.

[sgrice]

Common issue - seems to have greater ramifications for diesels than gas - check it out here:
https://xoutpost.com/bmw-sav-forums/...-diy-pics.html

[Entropy]

Good thing it stuck open and not closed!

[basilray]

Had mine done about 2 months ago. Book time on the thermostat is about 3.5hrs.

Cost me $550 all-in w/ my Indy ($95/hr labor).

I'd have gone about it myself, but the EGR cooler sits right there over the thermostat on the M57. Just more than I wanted to chew off at home in my garage. It's easier on the gassers.

[garagelogician]

Originally Posted by basilray

Had mine done about 2 months ago. Book time on the thermostat is about 3.5hrs.

Cost me $550 all-in w/ my Indy ($95/hr labor).

I'd have gone about it myself, but the EGR cooler sits right there over the thermostat on the M57. Just more than I wanted to chew off at home in my garage. It's easier on the gassers.

What Indy shop do you go to in Minneapolis?

[Z06Luke]

Thanks guys, I'm ordering one today and I will do it myself.

[Ozer]

Its probably your main thermostat but... worth a try to look into EGR cooler thermostat first since it also fails and its so much easier and cheaper to change.
Part #8 on here: RealOEM.com - Online BMW Parts Catalog

https://www.youtube.com/watch?v=ZhtfKliAkiU

[daytonatrbo]

Originally Posted by Ozer

Its probably your main thermostat but... worth a try to look into EGR cooler thermostat first since it also fails and its so much easier and cheaper to change.
Part #8 on here: RealOEM.com - Online BMW Parts Catalog

https://www.youtube.com/watch?v=ZhtfKliAkiU

xdrive35D doesn't even have that assembly. You are looking at info for the wrong motor/region.

[danosll]

reaching and maintaining operating temperature is crucial for proper DPF regeneration . bad thermostat is common and will result is blocked DPF. 35D doesnt have a thermostat on egr cooler but instead a divertor valve inside with a vacum actuator. make sure divertor valve moves freely. if your motor hasnt been reaching proper temp for a while due to bad thermostat. you probably have a seized divertor valve as well .you can lube it and free it up you have to remove egr cooler to change thermostat anyway.