Quote:
Originally Posted by youngsj
Hi Guys - I've got ~400 miles on my new M3 6MT sedan and I'm getting this subtle groan/whirring noise coming from the rear (I think it's on the driver's side rear). At first I thought it might be a bearing, but I gave up on that theory because it goes away the instant I take it out of gear or depress the clutch.
Believe it or not, but the noise occurs in any gear...but only at 43 miles per hour!
It does not make the sound unless you are in gear...and although it will make the noise in any gear at 43 mph, it is most pronounced while in 4th. I think this is because 43 mph in 4th is a pretty even-tempered and quiet ride (in other words not-too-fast and not-too-slow). Also, it is best reproducible if I am feathering the gas...it generally goes away if I press firmly on the gas, and also generally goes away if I let off the gas totally (engine braking).
I've done a lot of searching on this noise on the internet and within these forums, and I've read a few posts where people describe a slight clunking, or some people describe a minor grinding when turning...my noise is not like that. The noise I'm hearing occurs regardless of whether I'm going straight or in a turn, and it sounds like a groaning/whirring sound.
I took it to my dealer today, and took the shop foreman for a road test. Luckily he did say he could hear it. He said he was going to contact BMW and also try to drive a few others (they've got a coupe on the lot)...and then he'd give me a call with an update.
Anyways...it is a quiet sound - but my commute is largely back roads, so I'm frequently in 4th going between 40-50 mph and so I hear this noise all the time - it's bugging the crap out of me.
Thanks for any help you guys can offer.
|
The E46 M3 used to have the same issue... a change of differential oil type cured it.