DIY: Fix Your Leaking Differential

jvictormp · 06-18-2021, 06:57 PM

Well, my car axle seals seemed like that too. But there was no stains around them, so I guessed that it could be anything but a leakage. Air flow would drag diff fluid to some place down there, but simply there were none.

So I cleaned it up with some cloth soaked with diesel, and after 500 miles, it is still clean.

jvictormp · 06-18-2021, 07:30 PM

Sorry, if you're not meaning the axle itself, but the area around, then you may have a leaking seal.

About the driveshaft, there's no problem on disconnecting from the gearbox. Just number all the bolts and nuts to return them to same place, and be careful on lowering it. Better if you have another person to help you holding it, but you can do it with jack stands or wooden blocks by yourself.

///Mobbin · 03-02-2022, 11:19 AM

Theodore thank you for this informative DIY! I'm starting to chronicle the process of installing an OS Giken differential - LINK to Thread - and will be utilizing some of your tips here. I'm curious if you happen to know the differential carrier bearing/race part numbers for our diffs? Any other tips you have for me would be greatly appreciated as well.

Theodore · 03-02-2022, 01:26 PM

I don't think BMW sells those parts separately. You can buy them from the aftermarket and one of those companies also made this video that might be helpful:

MPower7 · 10-11-2022, 07:56 PM

Great write up need to do the job. Is it recommended to get new torx diff bolts for this job? Do only cars built 09 and before use the counter balance bolts? Do they need to be torqued in a star pattern? Also how do you reinstall the nut flange?

E90SpcGryM3 · 10-20-2022, 09:00 PM

can someone explain the purpose of counting the threads? wont it count 10 rotations regardless of how you put the nut back on? great write up OP

MPower7 · 11-05-2022, 01:53 AM

Just did the pinion seal job today. What a pain in the ass to remove the full exhaust and shielding, etc. I do have one concern. I did find on black bolt of the 6 securing driveshaft to the pinion. I made a mistake my not marking the bolt all the way down to the pinion.

My pinion is marked blue, that means it has a black bolt. BMW tis says to line up the black bolt with the mark however the mark on my pinion is in the middle of the two bolts and not exactly lines up seen below. The only logical place to put the black bolt was where I put it.

Road test went smooth, no sound from drivetrain at all but still curious to hear your thoughts here.

06-18-2021, 06:57 PM	#23
jvictormp Captain 881 Rep 787 Posts Drives: 2008 M3 E92 6MT Join Date: Dec 2018 Location: Brazil iTrader: (0)	Well, my car axle seals seemed like that too. But there was no stains around them, so I guessed that it could be anything but a leakage. Air flow would drag diff fluid to some place down there, but simply there were none. So I cleaned it up with some cloth soaked with diesel, and after 500 miles, it is still clean.
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06-18-2021, 07:30 PM	#24
jvictormp Captain 881 Rep 787 Posts Drives: 2008 M3 E92 6MT Join Date: Dec 2018 Location: Brazil iTrader: (0)	Sorry, if you're not meaning the axle itself, but the area around, then you may have a leaking seal. About the driveshaft, there's no problem on disconnecting from the gearbox. Just number all the bolts and nuts to return them to same place, and be careful on lowering it. Better if you have another person to help you holding it, but you can do it with jack stands or wooden blocks by yourself.
	Appreciate 0 Quote

03-02-2022, 11:19 AM	#25
///Mobbin Colonel 1478 Rep 2,672 Posts Drives: m3 Join Date: Jul 2011 Location: Houston iTrader: (3)	Theodore thank you for this informative DIY! I'm starting to chronicle the process of installing an OS Giken differential - LINK to Thread - and will be utilizing some of your tips here. I'm curious if you happen to know the differential carrier bearing/race part numbers for our diffs? Any other tips you have for me would be greatly appreciated as well. __________________ 2021 Alfa Romeo Stelvio Quadrifoglio \| 2.9L \| Trofeo White Tri-Coat \| 8-spd
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03-02-2022, 01:26 PM	#26
Theodore Lieutenant 669 Rep 412 Posts Drives: 2011.5 E92 M3 Join Date: Oct 2015 Location: Tampa Bay, FL iTrader: (6)	I don't think BMW sells those parts separately. You can buy them from the aftermarket and one of those companies also made this video that might be helpful: __________________ What I Wish I Knew When I First Bought My E9X M3 Can Be Found Here E9X M3 Exact Original Equipment (OE) Equivalent Parts Can Be Found Here E9X M3 Common Torque Specs Can Be Found Here E9X M3 "Factory" Tools Can Be Found Here Last edited by Theodore; 03-02-2022 at 01:34 PM..
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10-11-2022, 07:56 PM	#27
MPower7 First Lieutenant 90 Rep 363 Posts Drives: 11' e92 M3 Join Date: Apr 2008 Location: SF iTrader: (1)	Great write up need to do the job. Is it recommended to get new torx diff bolts for this job? Do only cars built 09 and before use the counter balance bolts? Do they need to be torqued in a star pattern? Also how do you reinstall the nut flange?
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10-20-2022, 09:00 PM	#28
E90SpcGryM3 Private 3 Rep 75 Posts Drives: 11’ E90 M3 ZCP Slicktop 6spd Join Date: Oct 2021 Location: NY iTrader: (1)	can someone explain the purpose of counting the threads? wont it count 10 rotations regardless of how you put the nut back on? great write up OP
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11-05-2022, 01:53 AM	#29
MPower7 First Lieutenant 90 Rep 363 Posts Drives: 11' e92 M3 Join Date: Apr 2008 Location: SF iTrader: (1)	Just did the pinion seal job today. What a pain in the ass to remove the full exhaust and shielding, etc. I do have one concern. I did find on black bolt of the 6 securing driveshaft to the pinion. I made a mistake my not marking the bolt all the way down to the pinion. My pinion is marked blue, that means it has a black bolt. BMW tis says to line up the black bolt with the mark however the mark on my pinion is in the middle of the two bolts and not exactly lines up seen below. The only logical place to put the black bolt was where I put it. Road test went smooth, no sound from drivetrain at all but still curious to hear your thoughts here.
	Appreciate 0 Quote