Temperature creep under load

[8000RPM]

I just ordered a new BMW unit. It would be nice if this fixes my problem. It’s 14 years old so its time to change it anyway in the event there is no change.

My vote still goes to the radiator.

[COVID-19]

I just ordered a new BMW unit. It would be nice if this fixes my problem. It’s 14 years old so its time to change it anyway in the event there is no change.

Make sure you clean the condenser while the radiator is out.

[0-60motorsports]

My radiator is around 30k kms old and looks mint. Just cleaned it any way and the oil cooler too which also looked mint with no leaks. Both have no bent fins either. I’ll update on Monday or Tuesday if it fixed the issue or not.

[old///MFanatic]

Curious if you tried Red Line "Water Wetter" and how did the system temps react?

[FBloggs]

To the op. I would recomend that you pressure test the coolant circuit, test the coolant for combustion gasses and peer down each cylinder looking for a super clean piston crown.
Possible headgasket breach...small at this time.

[8000RPM]

Interesting, thanks for the suggestion. I requested a new test kit from Blackstone and will post back up results. I don’t have a pressure tester but maybe my local Autozone has one?

BTW, I just had my oil tested (13,500 mi) and came back in great shape.

To the op. I would recomend that you pressure test the coolant circuit, test the coolant for combustion gasses and peer down each cylinder looking for a super clean piston crown.
Possible headgasket breach...small at this time.

[ATB88]

Interesting, thanks for the suggestion. I requested a new test kit from Blackstone and will post back up results. I don’t have a pressure tester but maybe my local Autozone has one?

BTW, I just had my oil tested (13,500 mi) and came back in great shape.

wowow you're running near the "BMW recommended" oil change intervals? that's wild. curious: how much extra oil did you have to add over the course of those 13,500 miles?

[8000RPM]

I just picked it up recently and that’s what the previous owner did but I plan on doing 1/2 that interval. According to the previous owner, he didn’t have to add any. I ran the blackstone to see where the motor currently sits. According to those guys, the oil looks great.

[heinzboehmer]

I just picked it up recently and that’s what the previous owner did but I plan on doing 1/2 that interval. According to the previous owner, he didn’t have to add any. I ran the blackstone to see where the motor currently sits. According to those guys, the oil looks great.

Low lead levels do not necessarily correspond to the bearings being in good shape. It's possible that the lead coating is completely worn through. Copper is a bit high too.

[Dash1]

A 2006 M3 with no prior bearing service @ 115k miles should have the bearings done. Regardless of UOA.

[8000RPM]

I was going to do them anyway but I had not thought of that. Scary!

Low lead levels do not necessarily correspond to the bearings being in good shape. It's possible that the lead coating is completely worn through. Copper is a bit high too.

[WOLFN8TR]

A 2006 M3 with no prior bearing service @ 115k miles especially considering “BMW recommended" oil change intervals were followed.

Fixed...😬

[COVID-19]

A 2006 M3 with no prior bearing service @ 115k miles should have the bearings done. Regardless of UOA.

I replaced mine at 60k miles bc I couldn’t sleep at night.

[mrgizmo04]

Down the same thought of FBIoggs, compression test to see headgasket condition.

Sent from my SM-G950U using Tapatalk

[Zekarus]

I have nearly the same behaviour and changed my head gasket a few months ago. Not that it couldn't be bad again but how could a bad head gasket get the water temp colder when driving down a hill?

As I'm home again I will try to see today if I can find the problem.