Rotating Scratching Sound -- Rear Differential?

vifferfun · 04-10-2017, 08:22 PM

Hi Everyone,

I'm having an issue with my 2012 335i sedan. While driving, my car makes a rotating scratching sound that seems like it's coming from the right rear area. BMW has looked at it an thought it may be the rear differential, but rear differential is $5000! Has anyone else had an issue with their rear differential? The scratching sound seems to be worse when it's cold and dry outside, and it's more prominent when the car is under throttle at slower speeds below 70 km/h.

Thanks!

tom73 · 04-10-2017, 10:07 PM

Could be the diff, pinion or axle bearing. Any different when turning compared to going straight?

vifferfun · 04-11-2017, 12:23 AM

No, it seems to be the same regardless or whether or not I'm turning. It seems like the sound is coming from the rear. I have RWD by the way. Thanks!

RoundelM3 · 04-11-2017, 07:04 AM

It could also be a wheel bearing - you might have them check that. Aside from a bearing, it might even be one of the CV joints on your independent rear suspension, or it could be something as simple as a rock or other debris caught in your rear wheel and making contact as it rotates.

vifferfun · 04-11-2017, 02:09 PM

Htanks, I'll have them take a look into those possibilities as well. It's weird that the sound isn't consistent . . . the scratchhing kind of pulsates LOUD soft LOUD soft as it rotates, and the intensity of sound varies. It seems like it is loudest when I'm pressing on the accelerator at lower RPMs.

Thanks!

04-10-2017, 08:22 PM	#1
vifferfun Private 10 Rep 84 Posts Drives: 2012 BMW 335i Sedan 6MT Join Date: Jul 2011 Location: Toronto, ON iTrader: (0)	Rotating Scratching Sound -- Rear Differential? Hi Everyone, I'm having an issue with my 2012 335i sedan. While driving, my car makes a rotating scratching sound that seems like it's coming from the right rear area. BMW has looked at it an thought it may be the rear differential, but rear differential is $5000! Has anyone else had an issue with their rear differential? The scratching sound seems to be worse when it's cold and dry outside, and it's more prominent when the car is under throttle at slower speeds below 70 km/h. Thanks!
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04-10-2017, 10:07 PM	#2
tom73 Private 17 Rep 64 Posts Drives: VW Passat Join Date: Mar 2017 Location: South Jersey iTrader: (0)	Could be the diff, pinion or axle bearing. Any different when turning compared to going straight?
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04-11-2017, 12:23 AM	#3
vifferfun Private 10 Rep 84 Posts Drives: 2012 BMW 335i Sedan 6MT Join Date: Jul 2011 Location: Toronto, ON iTrader: (0)	No, it seems to be the same regardless or whether or not I'm turning. It seems like the sound is coming from the rear. I have RWD by the way. Thanks!
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04-11-2017, 07:04 AM	#4
RoundelM3 Major General 1837 Rep 6,990 Posts Drives: 15 F80 M3, 22 G01 X3 30i Join Date: Apr 2010 Location: Clayton, NC iTrader: (2) Garage List 2022 BMW X3 [9.83] 2015 BMW M3 [6.50]	It could also be a wheel bearing - you might have them check that. Aside from a bearing, it might even be one of the CV joints on your independent rear suspension, or it could be something as simple as a rock or other debris caught in your rear wheel and making contact as it rotates. __________________ 2015 F80 ///M3 Sedan 7DCT Tanzanite, 2022 X3 sDrive30i 8AT Brooklyn Grey
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04-11-2017, 02:09 PM	#5
vifferfun Private 10 Rep 84 Posts Drives: 2012 BMW 335i Sedan 6MT Join Date: Jul 2011 Location: Toronto, ON iTrader: (0)	Htanks, I'll have them take a look into those possibilities as well. It's weird that the sound isn't consistent . . . the scratchhing kind of pulsates LOUD soft LOUD soft as it rotates, and the intensity of sound varies. It seems like it is loudest when I'm pressing on the accelerator at lower RPMs. Thanks!
	Appreciate 0 Quote