Problem with rear differential

[BossM5]

Hello everybody!
I have an 12' F10 M5 and have some issues regarding rear differential lately. Sometimes it seems like it won't lock and let me slide, and sometimes it works fine.

Like for example if i have traction fully off and floor it from standstill shouldn't it leave tire smoke behind the car just like any other m5?

Appreciate the help

[Fast400]

Should lite up...did you completely turn off the DSC? Keep holding the DSC button until completely off. If you've done that, there may be an issue

[BossM5]

Originally Posted by Fast400

Should lite up...did you completely turn off the DSC? Keep holding the DSC button until completely off. If you've done that, there may be an issue

DSC is fully off...

[Noggie]

Think you need to be more specific.

Are you saying, no wheel spin at all or just one wheel spinning?

A diff has very few failures, typically the limited slip fails, making the diff fail to spinn on both wheels, however one wheel will spinn. the other option is catastrophic failure, I know, I had one spitting out parts on a car once.

A car not spinning is more lightly a clutch issue.
If the problem is intermittent, the DCT has two clutches, perhaps one of them is worn and the other not, which is why sometimes it works and sometimes, when you hit the bad clutch it does not work.

A tip.
If you go to BMW and have a clutch relearn done, be aware that if the diagnostic says the clutch needs to replaced, it will NOT let the car drive off before the clutch has been replaced. The car is essentially crippled by the Diagnostic tool and will lock the car in "limp home mode" until a successful clutch learn has been done.
So DO NOT do this unless you are prepared to leave the car there and cough up the money to replace the clutches.

[BossM5]

Originally Posted by Noggie

Think you need to be more specific.

Are you saying, no wheel spin at all or just one wheel spinning?

A diff has very few failures, typically the limited slip fails, making the diff fail to spinn on both wheels, however one wheel will spinn. the other option is catastrophic failure, I know, I had one spitting out parts on a car once.

A car not spinning is more lightly a clutch issue.
If the problem is intermittent, the DCT has two clutches, perhaps one of them is worn and the other not, which is why sometimes it works and sometimes, when you hit the bad clutch it does not work.

A tip.
If you go to BMW and have a clutch relearn done, be aware that if the diagnostic says the clutch needs to replaced, it will NOT let the car drive off before the clutch has been replaced. The car is essentially crippled by the Diagnostic tool and will lock the car in "limp home mode" until a successful clutch learn has been done.
So DO NOT do this unless you are prepared to leave the car there and cough up the money to replace the clutches.

It depends from time to time. Sometimes the wheels will spin just like normal, while other times it will feks spin in 2 gear and suddenly not spin when you shift to third.m
However if i try to do donuts it works perfectly fine

[Noggie]

Originally Posted by BossM5

It depends from time to time. Sometimes the wheels will spin just like normal, while other times it will feks spin in 2 gear and suddenly not spin when you shift to third.m
However if i try to do donuts it works perfectly fine

Well, if you are doing a burnout in second gear, changing up to third will be the other set of clutches.
I doubt you have a diff issue, probably a clutch issue.

Have you pulled any fault codes?
Where in Norway are you? I'm in Stavanger.