Thermostat OEM Audi or OEM BMW

Thermostat is an bmw part so its fine

03’ E46 318ci with 130k miles and no issues with the whole cooling system. Neither the thermostat.

I was instructed by a friend who had some of m47 and m57, to buy thermostat only original from bmw, because everything else doesn't work as long or good.

Not the water pump but I just had my thermostat replaced under the extended warranty. I was slowly losing coolant with no discernable leak.

I just got this done and Audi quoted me $2500 for just the thermostat. Mine was covered by the extended warranty Audi has on all water pumps leaks.

The replacement thermostat came from BMW. No problems this time.

Had this happen to our 2018 Q5 a few months back, 35k miles on the SUV. Thermostat issue plus some other stuff.

My Q5 with 75,000 miles on it developed a leak in the water pump area. Initially Audi denied there was a leak, so I took pictures and showed it to them. Then they diagnosed it with thermostat leak.

I replaced the t-stat with a genuine part and again no luck.

Changed to genuine thermostat, no change. Needle tends to dip on higher load highway driving, but only occasionally. Obd temp is between 77C-88C.