rear diff failure and 2nd evap replacement

coloradoe92m3 · 03-26-2014, 02:49 PM

Well approaching 90k miles, no track, no launch control use but consistently fun, legal hard driving and found today cracked rear subframe. Car was making worst noise for two weeks. Also second time evap cooler replaced. First at 30k. Problem is where a/c unit is. Its a huge procedure to replace. Subframe replacement is prob nearing 5-7 k. I'm glad I got BMW extended warranty.

I hadn't heard of diff cracks so wanted to share.

dnvrdrvr · 03-26-2014, 03:13 PM

Wait, didn't you just post about the bearing issue being over-inflated?? Thought you were shopping dealers for minor issues?

W/// · 03-26-2014, 03:16 PM

Quote:

Originally Posted by coloradoe92m3

Well approaching 90k miles, no track, no launch control use but consistently fun, legal hard driving and found today cracked rear subframe. Car was making worst noise for two weeks. Also second time evap cooler replaced. First at 30k. Problem is where a/c unit is. Its a huge procedure to replace. Subframe replacement is prob nearing 5-7 k. I'm glad I got BMW extended warranty.

I hadn't heard of diff cracks so wanted to share.

Wait wait wait. You are talking about 2 very different things.

Subframe crack or diff bolt?

coloradoe92m3 · 03-26-2014, 03:19 PM

Subframe crack. A/c was minor issue and so was this sound. I meant no engine problems or knowingly big repairs. My a/c wasn't very cold. That's minor. Grumbling sound thought would be simple . Shocked at crack

FazerBoy · 03-26-2014, 03:27 PM

Wow - that's the first I've heard of.

Is this with the stock subframe bushings and suspension etc or has it been modified?

Malek@MRF · 03-26-2014, 03:30 PM

Quote:

Originally Posted by W///

Wait wait wait. You are talking about 2 very different things.

Subframe crack or diff bolt?

Not necessarily. The sub-frame damage in a lot of cases occurs because the diff has also failed at its mounting points creating massive stress.

Quote:

Originally Posted by FazerBoy

Wow - that's the first I've heard of.

Is this with the stock subframe bushings and suspension etc or has it been modified?

I've personally seen more damaged sub-frames, broken differential bolts and damaged differentials than blown motors from rod bearings. It's a pretty prominent problem.

IzzyGray · 03-26-2014, 03:37 PM

Quote:

Originally Posted by Malek@MRF

Not necessarily. The sub-frame damage in a lot of cases occurs because the diff has also failed at its mounting points creating massive stress.

I've personally seen more damaged sub-frames, broken differential bolts and damaged differentials than blown motors from rod bearings. It's a pretty prominent problem.

What would you recommend for a proactive/preventative solution

Malek@MRF · 03-26-2014, 03:39 PM

Quote:

Originally Posted by IzzyGray

What would you recommend for a proactive/preventative solution

Sub-frame bushings with upgraded differential bushings. It will 100% eliminate the problem.

There are over 20 forum members now that we have done this work for with our own MRF solid Sub-Frame bushings.

IzzyGray · 03-26-2014, 03:52 PM

Quote:

Originally Posted by Malek@MRF

Sub-frame bushings with upgraded differential bushings. It will 100% eliminate the problem.

There are over 20 forum members now that we have done this work for with our own MRF solid Sub-Frame bushings.

PM me prices for parts, shipped to 53172? How involved is the swap?

Vic311 · 03-26-2014, 03:53 PM

Quote:

Originally Posted by W///

Wait wait wait. You are talking about 2 very different things.

Subframe crack or diff bolt?

+1

Usually subframe damage is accompanied by diff damage, in which case he's looking at a very costly repair, if both need replacing. Hopefully OP is under warranty.

spr · 03-27-2014, 03:11 PM

Have any pics of what and where to look for? I have a sloppy rear end feeling and haven't yet had the time to look under there. I was thinking bushings were bad but there is creaking from rear area around corners now

FogCityM3 · 03-27-2014, 03:43 PM

Differential stress will be manifested in a "popping" sound when shifting at low RPM (at least that's what I experienced). Almost sounds like the exhaust but it isn't. I brought it in when started hearing this and dealer gave a clean bill of health, one month later differential bolt snapped. Diff, subframe, fuel tank and one of the controller arms replaced under warranty ($13k parts & labor shadow charge). Also had AC evaporator replaced due to a leak caused by a rock chip/debris.

spr · 03-27-2014, 03:45 PM

Quote:

Originally Posted by FogCityM3

Differential stress will be manifested in a "popping" sound when shifting at low RPM (at least that's what I experienced). Almost sounds like the exhaust but it isn't. I brought it in when started hearing this and dealer gave a clean bill of health, one month later differential bolt snapped. Diff, subframe, fuel tank and one of the controller arms replaced under warranty ($13k parts & labor shadow charge). Also had AC evaporator replaced due to a leak caused by a rock chip/debris.

WOW!

lutfy · 03-27-2014, 03:55 PM

Quote:

Originally Posted by Malek@MRF

Not necessarily. The sub-frame damage in a lot of cases occurs because the diff has also failed at its mounting points creating massive stress.

If logic prevails, Diff is part of drivetrain and covered under extended warranty (CPO or such). so in this case, it would also cover the subframe?

OP curious about your finding.

Thx,

Lutfy

spr · 03-27-2014, 03:57 PM

Quote:

Originally Posted by lutfy

If logic prevails, Diff is part of drivetrain and covered under extended warranty (CPO or such). so in this case, it would also cover the subframe?

OP curious about your finding.

Thx,

Lutfy

This was my thinking. I also have extended warranty and wanted to have rear end checked out since it's so squirmy.

Malek@MRF · 03-27-2014, 06:34 PM

Quote:

Originally Posted by lutfy

If logic prevails, Diff is part of drivetrain and covered under extended warranty (CPO or such). so in this case, it would also cover the subframe?

OP curious about your finding.

Thx,

Lutfy

Unfortunately the dealers aren't keen on doing this repair as they have told many people the problem is a result of "abuse". A lot of the higher mileage cars were denied by warranty when the diff and sub-frame were damaged.

s85e90 · 03-27-2014, 06:43 PM

Quote:

Originally Posted by Malek@MRF

Unfortunately the dealers aren't keen on doing this repair as they have told many people the problem is a result of "abuse". A lot of the higher mileage cars were denied by warranty when the diff and sub-frame were damaged.

I could maybe understand the denying the diff coverage, but the cracked subframes???? After they just finished the e46 recall campaign only a few years back?

03-26-2014, 02:49 PM	#1
coloradoe92m3 Banned 31 Rep 496 Posts Drives: m3 Join Date: Mar 2014 Location: u.s iTrader: (0)	rear diff failure and 2nd evap replacement Well approaching 90k miles, no track, no launch control use but consistently fun, legal hard driving and found today cracked rear subframe. Car was making worst noise for two weeks. Also second time evap cooler replaced. First at 30k. Problem is where a/c unit is. Its a huge procedure to replace. Subframe replacement is prob nearing 5-7 k. I'm glad I got BMW extended warranty. I hadn't heard of diff cracks so wanted to share. Last edited by coloradoe92m3; 03-26-2014 at 03:04 PM..
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03-26-2014, 03:13 PM	#2
dnvrdrvr Captain Obvious 90 Rep 977 Posts Drives: 2018 VW GTI SE Join Date: Jul 2009 Location: Denver, CO iTrader: (9)	Wait, didn't you just post about the bearing issue being over-inflated?? Thought you were shopping dealers for minor issues? __________________ Just a girl and her 863 ponies... 2013 Santorini M3, 2016 328i Alpine White Wagon (Lab hauler), 199x wrapped E36 M3 (because racecar) ///M-Flight
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03-26-2014, 03:19 PM	#4
coloradoe92m3 Banned 31 Rep 496 Posts Drives: m3 Join Date: Mar 2014 Location: u.s iTrader: (0)	Subframe crack. A/c was minor issue and so was this sound. I meant no engine problems or knowingly big repairs. My a/c wasn't very cold. That's minor. Grumbling sound thought would be simple . Shocked at crack
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03-26-2014, 03:27 PM	#5
FazerBoy Lieutenant 50 Rep 511 Posts Drives: BMW E92 M3 Join Date: Jul 2008 Location: London, UK iTrader: (0)	Wow - that's the first I've heard of. Is this with the stock subframe bushings and suspension etc or has it been modified?
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03-27-2014, 03:11 PM	#11
spr Major 94 Rep 1,089 Posts Drives: F80 M3; e92 ESS650+ M3 Join Date: Nov 2008 Location: San Diego iTrader: (1)	pics? Have any pics of what and where to look for? I have a sloppy rear end feeling and haven't yet had the time to look under there. I was thinking bushings were bad but there is creaking from rear area around corners now __________________ F80 M3 HRE FF04 275/305.
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03-27-2014, 03:43 PM	#12
FogCityM3 Colonel 500 Rep 2,400 Posts Drives: M3 (E90) & Porsche GT3 RS Join Date: Feb 2012 Location: San Francisco iTrader: (0)	Differential stress will be manifested in a "popping" sound when shifting at low RPM (at least that's what I experienced). Almost sounds like the exhaust but it isn't. I brought it in when started hearing this and dealer gave a clean bill of health, one month later differential bolt snapped. Diff, subframe, fuel tank and one of the controller arms replaced under warranty ($13k parts & labor shadow charge). Also had AC evaporator replaced due to a leak caused by a rock chip/debris.
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