Questions/Concerns About Transmissoin (LSD) Issue on Potential E90 M3 Purchase

hey guys,

I've been looking for an E90 M3 for quite some time and I recently came across a Jerez Black/Bamboo 2011 E90 M3 DCT(11/2010 Build Date) that seems like a pretty good deal. I asked for the Carfax and service records of the car and found a few issues that the original owner had to take care of.

At 8,067 miles - Grating noise while cornering (in service for 3 days)

Here's the biggest concern
At 9,159 miles - Grating noise from final drive unit (HAG)
(limited-slip differential)unpleasant noise (in service for 18 days)

Should I be worried about these issues? The warranty expires in 01/2015 so I do have some time to claim warranty but what if the problems happen right after warrnty? TIA for any inputs/thoughts

My two cents: if the car has been trouble-free since then, I wouldn't worry about it. Sounds like the problem was corrected long ago.

I think the noise that was heard early on in its life was common.

Usually adding the friction modifier solved the problem.

BzsBimmer wrote

I think the noise that was heard early on in its life was common.

Usually adding the friction modifier solved the problem.

Yes, but 18 days in the shop leads me to believe they maybe replaced the rear diff. Either way, if the problem didn't return since then I wouldn't worry.

Thank you guys for the inputs. It does make me feel much better about purchasing the car. I hope I can get the deal done in the next week or so and I'll post some pics then!

This from the Technical Service Bulletin posted here in 2012.
http://www.m3post.com/forums/showpost.php?p=12387880&postcount=9

If you follow the driving pattern recommended:
"With the vehicle at operating temperature
Drive in tight circles (20 circles in each direction)"
I know this is after changing the fluid, but try it out in a parking lot before you purchase. You might get a little noise as the M Lock differential does it's job. The sound should be mild and noticeable with the music turned off. It should not happen all the time in normal driving.

I know that mine is working every once in a while, even with 37k miles.

Hope to see you in the neighbor hood.

Power Train Instructor
Saddleback College
Mission Viejo, CA