Rear Seal Leak

wetzelgw · 06-29-2016, 08:14 PM

Hi All,

Long time lurker, first time poster. I've tried searching for the past hour or so and haven't had luck finding the answers I'm looking for.

I bought a 2009 135i MT with 65k miles about 3 months ago. I took it to an indy for a PPI, and they came back with a few things, nothing enough to deter purchase. I brought it back to them to replace the leaking OFHG seal, as well as do a walnut shell blast. They also put some dye in the oil to see if there were any additional leaks. About 6 weeks go by and I bring it back to the indy to mount some new tires and check the oil dyes. Prior to replacing the OFHG I did notice some oil on the ground, but haven't seen any since, so I wasn't expecting anything to come from the oil dyes. Lo and behold, the indy calls me up and not only do I have a rear seal leak, it's a 10 hour repair and it will run me $1300.

Searching hasn't come back with many hits, so I can't get a good feel for this, and I would really appreciate it if you guys could help me answer these questions:
- I saw a post on N54tech say they got an estimate of $650...don't know their location, but I'm in the Chicago suburbs. Is 10 hrs/$1300 a reasonable time/price estimate?
- I've seen lots about oil leaking from the OFHG and the Valve Cover, but almost nothing on this. How common is a leaking rear seal on the N54?
- I'm ok with a wrench, but don't have the time/space/tools to tackle something like this on my own. My indy said it's 'leaking a fair amount', but I haven't seen anything on the garage floor, or had to add any oil. How urgent is this repair?

Thank you,
Greg

ayao · 06-30-2016, 12:03 AM

http://www.n54tech.com/forums/showthread.php?t=40644

justin4 · 07-12-2016, 04:35 PM

I'm at 68k and my mechanic noticed mine was leaking as well. He adviced me when I was ready for the service to replace the flywheel and transmission as well since they have to drop the transmission. You might want to look into that as well so you can save some money on labor in the future.

PA135i · 07-12-2016, 07:42 PM

Mine leaked last year and ruined my clutch. I was lucky BMW went 50/50 with me on the repair since I was out of warranty.

Dackelone · 07-12-2016, 08:03 PM

If its not leaking that badly... I would wait. Your gonna need to replace the clutch when you do this job. Or you will be back there again(sooner rather than later). You might also want to replace the flywheel or at least resurface it - when you do this job.

A rear crankshaft seal seems to be kind of common. Especially on 1M's for some reason. Also this bad seal can cause some weird fluttering noises when the AC is on and the revs fall from 2,500 to 1,700 rpms.

good luck,
Dackel

Trptguy · 07-13-2016, 08:05 PM

mine has a small leak as well. Since I am at 150k i know that my clutch will be done by the end of the summer, figure I will get it done then.

06-29-2016, 08:14 PM	#1
wetzelgw Registered 1 Rep 2 Posts Drives: 2009 BMW 135i Join Date: May 2016 Location: Chicago suburbs iTrader: (0)	Rear Seal Leak Hi All, Long time lurker, first time poster. I've tried searching for the past hour or so and haven't had luck finding the answers I'm looking for. I bought a 2009 135i MT with 65k miles about 3 months ago. I took it to an indy for a PPI, and they came back with a few things, nothing enough to deter purchase. I brought it back to them to replace the leaking OFHG seal, as well as do a walnut shell blast. They also put some dye in the oil to see if there were any additional leaks. About 6 weeks go by and I bring it back to the indy to mount some new tires and check the oil dyes. Prior to replacing the OFHG I did notice some oil on the ground, but haven't seen any since, so I wasn't expecting anything to come from the oil dyes. Lo and behold, the indy calls me up and not only do I have a rear seal leak, it's a 10 hour repair and it will run me $1300. Searching hasn't come back with many hits, so I can't get a good feel for this, and I would really appreciate it if you guys could help me answer these questions: - I saw a post on N54tech say they got an estimate of $650...don't know their location, but I'm in the Chicago suburbs. Is 10 hrs/$1300 a reasonable time/price estimate? - I've seen lots about oil leaking from the OFHG and the Valve Cover, but almost nothing on this. How common is a leaking rear seal on the N54? - I'm ok with a wrench, but don't have the time/space/tools to tackle something like this on my own. My indy said it's 'leaking a fair amount', but I haven't seen anything on the garage floor, or had to add any oil. How urgent is this repair? Thank you, Greg
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06-30-2016, 12:03 AM	#2
ayao Thread killer 643 Rep 1,896 Posts Drives: 1M Join Date: Aug 2011 Location: CA iTrader: (2)	http://www.n54tech.com/forums/showthread.php?t=40644
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07-12-2016, 04:35 PM	#3
justin4 Private First Class 14 Rep 119 Posts Drives: m235i white Join Date: Nov 2015 Location: Irvine, CA --> Austin, TX iTrader: (0)	I'm at 68k and my mechanic noticed mine was leaking as well. He adviced me when I was ready for the service to replace the flywheel and transmission as well since they have to drop the transmission. You might want to look into that as well so you can save some money on labor in the future.
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07-12-2016, 07:42 PM	#4
PA135i Brigadier General 968 Rep 3,323 Posts Drives: 08 135i 08 CR-V Join Date: Dec 2007 Location: Pennsylvania iTrader: (0)	Mine leaked last year and ruined my clutch. I was lucky BMW went 50/50 with me on the repair since I was out of warranty. __________________ Sparkling Graphite Metallic / 6MT / Terracotta Boston Leather / Sport Package / Comfort Access system / Gray Poplar wood trim / Heated front seats / iPod and USB adapter / HD radio / Premium hi-fi system / OE Tuning / VRSF Intercooler & charge pipe / BMW Performance short shift kit / BMW M Performance Handbrake Handle / BMW Stainless steel pedals / V1 hardwired / rear sun shades *Pennsylvania 20 electoral votes*
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07-12-2016, 08:03 PM	#5
Dackelone European Editor 10589 Rep 22,992 Posts Drives: N54 e82 Join Date: Feb 2010 Location: Bayern, Germany iTrader: (1)	If its not leaking that badly... I would wait. Your gonna need to replace the clutch when you do this job. Or you will be back there again(sooner rather than later). You might also want to replace the flywheel or at least resurface it - when you do this job. A rear crankshaft seal seems to be kind of common. Especially on 1M's for some reason. Also this bad seal can cause some weird fluttering noises when the AC is on and the revs fall from 2,500 to 1,700 rpms. good luck, Dackel __________________ Dackel's European Delivery Museum Guide
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07-13-2016, 08:05 PM	#6
Trptguy Lieutenant 26 Rep 493 Posts Drives: '87 BMW 325ic, '08 BMW 135i Join Date: Jul 2011 Location: Littleton, MA iTrader: (0)	mine has a small leak as well. Since I am at 150k i know that my clutch will be done by the end of the summer, figure I will get it done then.
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