Rear Diff Output Shaft Leak Question

pyshin · 06-20-2021, 11:19 PM

I recently got my rod bearings changed by an indie mechanic who specializes in E46 M3's; while inspecting my Z4M he noticed that my rear diff output shaft seals had started weeping and advised to replace them soon. He also mentioned that rear diffs in E46 M3's had an issue of free-play that caused leaking at the same point, but was unsure if the diffs were the same.

I found this thread while researching the topic E46 M3 M-Diff vs E86 Z4M M-Diff ... differences? but nowhere did it mention Z4M's having the same free-play issue. I was hoping to get some clarification from the vets with experience before making my next appointment for the repair, thanks

tecnicaeleven · 06-21-2021, 07:29 AM

It does happen. I just had to replace the input shaft seal on the diff. Fairly common

06-20-2021, 11:19 PM	#1
pyshin Private First Class 111 Rep 160 Posts Drives: 97c2 Join Date: May 2020 Location: socal iTrader: (1)	Rear Diff Output Shaft Leak Question I recently got my rod bearings changed by an indie mechanic who specializes in E46 M3's; while inspecting my Z4M he noticed that my rear diff output shaft seals had started weeping and advised to replace them soon. He also mentioned that rear diffs in E46 M3's had an issue of free-play that caused leaking at the same point, but was unsure if the diffs were the same. I found this thread while researching the topic E46 M3 M-Diff vs E86 Z4M M-Diff ... differences? but nowhere did it mention Z4M's having the same free-play issue. I was hoping to get some clarification from the vets with experience before making my next appointment for the repair, thanks
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06-21-2021, 07:29 AM	#2
tecnicaeleven Private 38 Rep 69 Posts Drives: 07 Cooper S / 07 M Roadster Join Date: Dec 2014 Location: Nashville TN iTrader: (0)	It does happen. I just had to replace the input shaft seal on the diff. Fairly common
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