BMW M3 Forum (E90 E92)

BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   M3Post - BMW M3 Forum > E90/E92 M3 Technical Topics > Engine, Transmission, Exhaust, Drivetrain, ECU Software Modifications
 
Post Reply
 
Thread Tools Search this Thread
      09-08-2021, 12:22 PM   #1
GentleUser
New Member
10
Rep
9
Posts

Drives: 2010 E90 BMW M3
Join Date: Jun 2021
Location: Chicago

iTrader: (0)

Garage List
2010   [0.00]
E90 M3 differential problem

Hey guys! So a little big accident happened to me yesterday. Was driving on the highway, as I was going up the bridge didn't see some garbage on the road, when I saw it was too late to maneuver. Looks like some metal piece was laying there and it whipped my differential cooling fins and broke the cover off. Since it was a bridge I couldn't pull over and had to driver for another mile or so. Didn't see a lot of smoke coming out of it, but still differential was engaged without oil for some time. Obviously towed it back home.

Anybody had that problem? Is it "fixable" or do I have to buy a new differential? Any suggestions on where to order one?

Thanks in advance!
Attached Images
  
Appreciate 0
      09-08-2021, 01:18 PM   #2
Beyond_Ill
New Member
Beyond_Ill's Avatar
United_States
21
Rep
22
Posts

Drives: 2014 BMW 328i
Join Date: Jun 2021
Location: Houston, TX

iTrader: (0)

You can get a new differential cover from Turner Motorsport or ECS. It's possible that the diff could have sustained damage from the debris and running dry but there's no way to tell without having it inspected. If worse comes to worst and you need a new one, I'd recommend diffsonline
Appreciate 3
      09-08-2021, 01:49 PM   #3
tbuck
Captain
tbuck's Avatar
1186
Rep
940
Posts

Drives: 2011 E92 M3, 2010 MINI R55 JCW
Join Date: Feb 2020
Location: Huntsville

iTrader: (0)

No way would I try and run that again without full inspection and testing. New cover is the easy part, obviously. It may be fine, considering you were driving easy and without much in the way of load, but it could very well have overheated the clutches or done other damage. It would be best to pull it and let a qualified shop take a look. Sucks, no doubt, but better safe than sorry.

And diffsonline is definitely the best place to go.
__________________
Appreciate 2
      09-08-2021, 02:33 PM   #4
tdott
Brigadier General
3931
Rep
3,972
Posts

Drives: M3
Join Date: Nov 2010
Location: South FL / 6ix

iTrader: (4)

At first I wouldn't think it would be that bad as hopefully some fluid would still be on the gears while it coasted to a stop.

But looking at those pictures changed my mind, it looks pretty dry, not even a drip out the bottom, all the fluid is already gone.
Appreciate 2
tbuck1185.50
      09-08-2021, 03:06 PM   #5
KawBoy
Lieutenant
152
Rep
561
Posts

Drives: 2012 E92 M3
Join Date: May 2012
Location: SE FL

iTrader: (2)

I'd replace the cover and add oil. Run it and see what happens. If it doesn't sing, change the oil and enjoy it. If it sings... if you can live with that, it is all good. Otherwise replace it.
There are other things you can do, but you'd have to do step one and report back.
Good luck.
Appreciate 1
      09-08-2021, 06:53 PM   #6
tbuck
Captain
tbuck's Avatar
1186
Rep
940
Posts

Drives: 2011 E92 M3, 2010 MINI R55 JCW
Join Date: Feb 2020
Location: Huntsville

iTrader: (0)

Quote:
Originally Posted by tdott View Post
At first I wouldn't think it would be that bad as hopefully some fluid would still be on the gears while it coasted to a stop.

But looking at those pictures changed my mind, it looks pretty dry, not even a drip out the bottom, all the fluid is already gone.
I was thinking the same thing. Looks like the ring gear slung all the oil out as it spun. And it had to have been loud AF when it snapped the cover in half and took out a bolt as well.
__________________
Appreciate 1
      09-08-2021, 06:55 PM   #7
Redd
Brigadier General
3853
Rep
4,133
Posts

Drives: 2010 BMW E92 M3 Dakar Edition
Join Date: Jul 2015
Location: Malaysia

iTrader: (0)

M diff runs as an open diff unless it senses a speed differential between the rear wheels, and then it locks up. So it's possible the clutches were not engaged during the 1 mile dry run and you may not have suffered any major diff damage.

I'd replace the cover, clean the insides and fill it back up. Then run it and listen for abnormal diff noises. I have a feeling you may be fine. Good luck.
Appreciate 2
      09-08-2021, 07:02 PM   #8
GentleUser
New Member
10
Rep
9
Posts

Drives: 2010 E90 BMW M3
Join Date: Jun 2021
Location: Chicago

iTrader: (0)

Garage List
2010   [0.00]
Thanks guys. I dropped the car off at mechanics today. Will get a new cover, flush it and try to drive it. If it's ok, Will thank all car Gods for saving my ass. If not, looking at $5-6k bill for new diff
Appreciate 2
      09-08-2021, 07:25 PM   #9
Redd
Brigadier General
3853
Rep
4,133
Posts

Drives: 2010 BMW E92 M3 Dakar Edition
Join Date: Jul 2015
Location: Malaysia

iTrader: (0)

If you're going to have to replace the diff, just go OS Giken. It's cheaper, much higher performing, and has zero additional NVH.

Also there's this option for the diff cover:
https://store.vacmotorsports.com/mob...-m3-p4846.aspx

Lets see some street trash try to take that one out. Lol.
Appreciate 1
      09-08-2021, 11:02 PM   #10
Scharbag
Colonel
Scharbag's Avatar
Canada
2618
Rep
2,134
Posts

Drives: 2011 E92 M3
Join Date: Oct 2017
Location: Victoria

iTrader: (0)

Garage List
2011 BMW E92 M3  [0.00]
Quote:
Originally Posted by Redd View Post
If you're going to have to replace the diff, just go OS Giken. It's cheaper, much higher performing, and has zero additional NVH.

Also there's this option for the diff cover:
https://store.vacmotorsports.com/mobile/vac-motorsports-billet-differential-cover-bmw-e90e92e93-m3-p4846.aspx

Lets see some street trash try to take that one out. Lol.
$1K+ for a diff cover???

Sweet mother of pearl.

Diffsonline will be very expensive compared to just buying a used diff. Yeah f you really want to spend more, then spend more. But if the diff is good enough for you, a used one can be found pretty cheap. The diff is also really easy to change.

Cheers,
__________________

2011 E92 M3 - 6MT, ZCP, ZF LSD, ESS G1, Some other goodies...
Appreciate 0
      09-09-2021, 05:01 AM   #11
amrazM
mTekMods
amrazM's Avatar
United_States
2115
Rep
2,872
Posts

Drives: like a granny.
Join Date: Jan 2010
Location: Manhatan

iTrader: (1)

Diff is done, buy another one.
__________________
2011 Frozen Black/Fox Red E90 M3 650+WHP

G-Power Supercharged
First DCT to Manual Conversion Worldwide
KW CS, BBS RI-A, BW Headers, Snow 2.5
Appreciate 1
      09-09-2021, 11:04 AM   #12
tbuck
Captain
tbuck's Avatar
1186
Rep
940
Posts

Drives: 2011 E92 M3, 2010 MINI R55 JCW
Join Date: Feb 2020
Location: Huntsville

iTrader: (0)

Quote:
Originally Posted by Scharbag View Post
$1K+ for a diff cover???

Sweet mother of pearl.
That is for an aftermarket one, but the OE part is still $500 or so. Cheaper ones used on eBay.

https://www.ecstuning.com/b-genuine-...r/33112283010/
__________________
Appreciate 0
      09-09-2021, 11:32 AM   #13
Gossypiboma
Major
541
Rep
1,195
Posts

Drives: 13' M3 6MT 18' M3 CS
Join Date: Aug 2012
Location: The John

iTrader: (8)

Quote:
Originally Posted by GentleUser View Post
Thanks guys. I dropped the car off at mechanics today. Will get a new cover, flush it and try to drive it. If it's ok, Will thank all car Gods for saving my ass. If not, looking at $5-6k bill for new diff
Yes, finally someone logical. There's a great chance its perfectly fine. I'm betting there's no internal damage.
__________________
Appreciate 0
      09-09-2021, 04:33 PM   #14
tdott
Brigadier General
3931
Rep
3,972
Posts

Drives: M3
Join Date: Nov 2010
Location: South FL / 6ix

iTrader: (4)

Quote:
Originally Posted by Gossypiboma View Post
Yes, finally someone logical. There's a great chance its perfectly fine. I'm betting there's no internal damage.
Depends, there is a bit of risk but it could pay off.

If it doesn't pay off, then he is out the labor to swap the cover on, which I assume is the same as dropping the diff.

If he could have found a good used diff which usually comes with a diff cover for not much more, could save paying labor twice if it ends up being bad.
Appreciate 0
      09-09-2021, 08:45 PM   #15
Ubersmooth
Captain
Ubersmooth's Avatar
United_States
316
Rep
977
Posts

Drives: E92 335i
Join Date: Jul 2013
Location: NoVa

iTrader: (1)

I went through a broken diff recently, and the best/most affordable option is diffsonline.

After sending my old diff back for the core charge, it cost me about $1600 shipped for a stock rebuilt 3.85 differential including upgraded powerflex differential mounts.
Appreciate 0
      09-09-2021, 11:58 PM   #16
Scharbag
Colonel
Scharbag's Avatar
Canada
2618
Rep
2,134
Posts

Drives: 2011 E92 M3
Join Date: Oct 2017
Location: Victoria

iTrader: (0)

Garage List
2011 BMW E92 M3  [0.00]
Quote:
Originally Posted by Ubersmooth View Post
I went through a broken diff recently, and the best/most affordable option is diffsonline.

After sending my old diff back for the core charge, it cost me about $1600 shipped for a stock rebuilt 3.85 differential including upgraded powerflex differential mounts.
Ain't going to get a full core charge with a broken cover.
__________________

2011 E92 M3 - 6MT, ZCP, ZF LSD, ESS G1, Some other goodies...
Appreciate 0
      09-10-2021, 12:02 AM   #17
Ubersmooth
Captain
Ubersmooth's Avatar
United_States
316
Rep
977
Posts

Drives: E92 335i
Join Date: Jul 2013
Location: NoVa

iTrader: (1)

Quote:
Originally Posted by Scharbag View Post
Quote:
Originally Posted by Ubersmooth View Post
I went through a broken diff recently, and the best/most affordable option is diffsonline.

After sending my old diff back for the core charge, it cost me about $1600 shipped for a stock rebuilt 3.85 differential including upgraded powerflex differential mounts.
Ain't going to get a full core charge with a broken cover.
You reuse the cover for the differential he sends. I got a full refund keeping my cover which ended up being broken
Appreciate 0
      09-13-2021, 04:05 PM   #18
Vuu
Astronaut
Vuu's Avatar
514
Rep
732
Posts

Drives: E92 M3
Join Date: Nov 2018
Location: Orange County, CA

iTrader: (7)

I've got a used diff if someone's looking. Just replaced mine and have the OEM 3.85 (6MT) sitting in the garage.
__________________
Instagram | @undisclosedm3
"Never think that you are above taking out the trash."
Appreciate 0
      09-13-2021, 06:47 PM   #19
Redd
Brigadier General
3853
Rep
4,133
Posts

Drives: 2010 BMW E92 M3 Dakar Edition
Join Date: Jul 2015
Location: Malaysia

iTrader: (0)

OP any update on this please?
Appreciate 0
      09-14-2021, 12:35 AM   #20
GentleUser
New Member
10
Rep
9
Posts

Drives: 2010 E90 BMW M3
Join Date: Jun 2021
Location: Chicago

iTrader: (0)

Garage List
2010   [0.00]
Quote:
Originally Posted by Redd View Post
OP any update on this please?
Just got the cover. Waiting for BMW to get new bolts and oil. Should have in next 2 days. Will keep you posted.

Dealership said that new diff is $3800. Insane. Only 5 of them are coming to North America and they don't know when. If I'll have to do replacement probably will go with used one.
Appreciate 0
      09-14-2021, 08:52 AM   #21
Vuu
Astronaut
Vuu's Avatar
514
Rep
732
Posts

Drives: E92 M3
Join Date: Nov 2018
Location: Orange County, CA

iTrader: (7)

Quote:
Originally Posted by GentleUser View Post
Just got the cover. Waiting for BMW to get new bolts and oil. Should have in next 2 days. Will keep you posted.

Dealership said that new diff is $3800. Insane. Only 5 of them are coming to North America and they don't know when. If I'll have to do replacement probably will go with used one.
If you end up needing a replacement, diffsonline does rebuilds with a core exchange.

I also have a used OEM one available. Keep us updated.
__________________
Instagram | @undisclosedm3
"Never think that you are above taking out the trash."
Appreciate 0
      09-18-2021, 02:32 PM   #22
GentleUser
New Member
10
Rep
9
Posts

Drives: 2010 E90 BMW M3
Join Date: Jun 2021
Location: Chicago

iTrader: (0)

Garage List
2010   [0.00]
Quote:
Originally Posted by Vuu View Post
Quote:
Originally Posted by GentleUser View Post
Just got the cover. Waiting for BMW to get new bolts and oil. Should have in next 2 days. Will keep you posted.

Dealership said that new diff is $3800. Insane. Only 5 of them are coming to North America and they don't know when. If I'll have to do replacement probably will go with used one.
If you end up needing a replacement, diffsonline does rebuilds with a core exchange.

I also have a used OEM one available. Keep us updated.
So quick update. Replaced the cover, flushed it and drove it yesterday. Don't really have vibration or bad metal rattle, but it makes noise big time. Went for a 40 min joyride yesterday and came home with sad face. Because of the frequency of that diff noice, you barely can hear engine and exhaust. Wasn't pleasant at all. You can still go fast and it handled perfectly, but when you know it's not right, you can't enjoy it.

Will have to go with a new diff. Still thinking if I should go with OEM new, build one with different gear ratio or try to fix one I have.
Appreciate 1
Davisca4552207.50
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 05:10 PM.




m3post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST