Rear end knocking with initial accel/decel

FishTheStampede · 05-18-2019, 09:18 PM

When I get on the gas from a stop, the diff (according to my mechanic) makes a loud knock. My mechanic believes it's the diff.

Now I've been looking for a a replacement differential, but have been unable to find it.

I need help, has anyone had this issue? Does anyone know where I can procure a replacement diff?

Thanks in advance!

technician117 · 05-20-2019, 02:48 PM

Sounds like the diff mount bushing to me. Much cheaper to replace than the whole diff unit!

FishTheStampede · 05-21-2019, 06:37 PM

Quote:

Originally Posted by technician117

Sounds like the diff mount bushing to me. Much cheaper to replace than the whole diff unit!

I was under the car on a lift with a dude sitting inside reving on and off. I saw the diff moving up and down, but the sound seemed like it may have been coming from inside the housing, and not from a mount, but I'm really not sure.

Still, I'd really like to know where I can get a replacement. Anyone have an idea?

Studentloan_f32 · 12-13-2020, 06:17 AM

Quote:

Originally Posted by technician117

Sounds like the diff mount bushing to me. Much cheaper to replace than the whole diff unit!

How much would an estimate for a diff bushing ne?

technician117 · 12-13-2020, 06:33 AM

Quote:

Originally Posted by Studentloan_f32

How much would an estimate for a diff bushing ne?

I think the bushing itself isn't replaceable. (don't quote me though) So it's a matter of replacing the diff mount. The part is expensive but the labor shouldn't be. I haven't changed mine yet but it looks like an easy bolt off, bolt on situation. Maybe 1 hour shop labor?

Studentloan_f32 · 12-13-2020, 06:35 AM

Quote:

Originally Posted by technician117

Quote:

Originally Posted by Studentloan_f32

How much would an estimate for a diff bushing ne?

I think the bushing itself isn't replaceable. (don't quote me though) So it's a matter of replacing the diff mount. The part is expensive but the labor shouldn't be. I haven't changed mine yet but it looks like an easy bolt off, bolt on situation. Maybe 1 hour shop labor?

Glad to know the procedure isnt too bad. The bushings are replaceable, i believe a shop would need a special press to do it. Im not willing to shell out $1500+ for a billet mount😂😭

05-18-2019, 09:18 PM	#1
FishTheStampede Registered 1 Rep 3 Posts Drives: F10 M5 Join Date: May 2019 Location: South Korea iTrader: (0)	Rear end knocking with initial accel/decel When I get on the gas from a stop, the diff (according to my mechanic) makes a loud knock. My mechanic believes it's the diff. Now I've been looking for a a replacement differential, but have been unable to find it. I need help, has anyone had this issue? Does anyone know where I can procure a replacement diff? Thanks in advance!
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05-20-2019, 02:48 PM	#2
technician117 Captain 254 Rep 604 Posts Drives: 2000 M5, 2001 M5, 2013 M5 6MT Join Date: Jul 2018 Location: Buffalo iTrader: (1) Garage List 1990 BMW M5 [0.00] 2000 BMW M5 [0.00] 2013 BMW M5 [0.00]	Sounds like the diff mount bushing to me. Much cheaper to replace than the whole diff unit!
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