E92 M3 DCT Overheat!

[TheGr33k]

Originally Posted by Helmsman

Good input. Quite a few things done though, any idea what was the actual issue?

From everything I gathered and after reading transmission temps, we came to the conclusion of a failing temp/revolution sensor. Fluid was not low, clutch pack and clutches showed no signs of warp or excessive heat/friction outside of normal range. A good starting point would be to look at the the DCT thermostat and address if that is failing as Bimmerworld states that is a very potential culprit as well : https://www.bimmerworld.com/Cooling/Oil-Coolers/DCT-Transmission-Oil-Thermostat-E9X-M3-DCT.html

[Helmsman]

Originally Posted by TheGr33k

From everything I gathered and after reading transmission temps, we came to the conclusion of a failing temp/revolution sensor. Fluid was not low, clutch pack and clutches showed no signs of warp or excessive heat/friction outside of normal range. A good starting point would be to look at the the DCT thermostat and address if that is failing as Bimmerworld states that is a very potential culprit as well : https://www.bimmerworld.com/Cooling/...9X-M3-DCT.html

Got it. Replaced the Tstat earlier. The Clutch temp (revolution) sensor is the one occasionally going up and down. Seems to stabilize when driving a bit harder/revving up which makes me wonder about the fluid/spray supposely cooling the clutches (did you by any chance see what that looked like inside mate?). Will top up fluid during the week, see what happens.

[Redd]

I'm wondering, is there a way to bypass the DCT fluid thermostat? To have it permanently open so that fluid flows to DCT cooler 100% of the time. I live in a hot climate so warming up the DCT fluid is not so important.

[deansbimmer]

Originally Posted by Redd

I'm wondering, is there a way to bypass the DCT fluid thermostat? To have it permanently open so that fluid flows to DCT cooler 100% of the time. I live in a hot climate so warming up the DCT fluid is not so important.

Foolish IMO. The thermostatic control is desirable. It's easy to access, easy to replace, not an expensive part. Retain it.

[Redd]

Originally Posted by deansbimmer

Foolish IMO. The thermostatic control is desirable. It's easy to access, easy to replace, not an expensive part. Retain it.

Yessir... 😅

[Helmsman]

Originally Posted by TheGr33k

From everything I gathered and after reading transmission temps, we came to the conclusion of a failing temp/revolution sensor. Fluid was not low, clutch pack and clutches showed no signs of warp or excessive heat/friction outside of normal range. A good starting point would be to look at the the DCT thermostat and address if that is failing as Bimmerworld states that is a very potential culprit as well : https://www.bimmerworld.com/Cooling/Oil-Coolers/DCT-Transmission-Oil-Thermostat-E9X-M3-DCT.html

So turned out 0.3 liter was possible to squeeze in i.e. box was full so there goes my final hope out the window. Temp sensor continue to act. To make it clear I got the code and limp on my way from the shop....

They quoted 2k usd to drop the box and replace the sensor and while in there one of the hoses to sort a tiny leak. Might be my next action but will try a adaptation reset for the fun of it first.
Again box have done 40k calm miles so continue to refuse to believe the clutches actually slip.