How Often do Rear Main Seals Fail?
Joined: Jun 2010
Posts: 5,539
Likes: 6
From: McKinney, TX
Jimi 's car (who posted above) had a rear main seal let go and it cost him an engine. Or so it appears... I dont know what the first step of the failure was, but his rear main leaked all the way to the back of the car.
Of the countless clutch jobs I've done, I haven't seen a leak nor have I replaced the seal.
I would replace the seal on a high mile car, but only under these conditions:
You can safely remove the seal without scratching the delicate aluminum seal surface, or the delicate crankshaft surface.
You can put the new seal in, perfectly square, in its original distance.
You can put the seal in without distorting it in any way.
This is where a custom tool comes in handy.
Of the countless clutch jobs I've done, I haven't seen a leak nor have I replaced the seal.
I would replace the seal on a high mile car, but only under these conditions:
You can safely remove the seal without scratching the delicate aluminum seal surface, or the delicate crankshaft surface.
You can put the new seal in, perfectly square, in its original distance.
You can put the seal in without distorting it in any way.
This is where a custom tool comes in handy.
One thing I might add is what makes a really easy makeshift rear main seal driver for our cars is a PVC pipe fitting. I believe a 4" end cap is what I have to do RMS's on S2000's, but I'd have to confirm. It may actually be a section of 4" pipe with a 4" cap on the end to ensure it gets driven in squarely. Either way, you get the idea. This is a cheap alternative to buying a metal seal driving kit, especially if you only need one size driver.
Joined: Mar 2015
Posts: 1,370
Likes: 138
From: Cali
Off topic.. but, my '03 Tacoma Prerunner 4-cyl had a rear-main seal leak before I sold it for my current S2k (don't worry.. the buyer knew, after the PPI). Its' water pump was also going out.
Sold the Tacoma for $10k, got a GPW MY03 with 30k less miles than the Tacoma for $12k. Not too shabby of a trade.
(Tacoma was at 125k miles, the S2k was at 95k miles).
Since I do a lot of gardening and landscaping now as a hobby, I kinda miss the Tacoma, lol. It's difficult fitting half wine barrels in the passenger seat, big bags of soil and/or big plants in the S2k... but I get it done, haha.
So if you ever see an S2k driving around with a wine barrel in the passenger seat, or a pine or maple tree pressed up against and covering the windshield or poking out the window, it is most likely me.
Sold the Tacoma for $10k, got a GPW MY03 with 30k less miles than the Tacoma for $12k. Not too shabby of a trade.
(Tacoma was at 125k miles, the S2k was at 95k miles).
Since I do a lot of gardening and landscaping now as a hobby, I kinda miss the Tacoma, lol. It's difficult fitting half wine barrels in the passenger seat, big bags of soil and/or big plants in the S2k... but I get it done, haha.
So if you ever see an S2k driving around with a wine barrel in the passenger seat, or a pine or maple tree pressed up against and covering the windshield or poking out the window, it is most likely me.
Joined: Feb 2016
Posts: 22
Likes: 1
Jimi 's car (who posted above) had a rear main seal let go and it cost him an engine. Or so it appears... I dont know what the first step of the failure was, but his rear main leaked all the way to the back of the car.
Of the countless clutch jobs I've done, I haven't seen a leak nor have I replaced the seal.
I would replace the seal on a high mile car, but only under these conditions:
You can safely remove the seal without scratching the delicate aluminum seal surface, or the delicate crankshaft surface.
You can put the new seal in, perfectly square, in its original distance.
You can put the seal in without distorting it in any way.
This is where a custom tool comes in handy.
Of the countless clutch jobs I've done, I haven't seen a leak nor have I replaced the seal.
I would replace the seal on a high mile car, but only under these conditions:
You can safely remove the seal without scratching the delicate aluminum seal surface, or the delicate crankshaft surface.
You can put the new seal in, perfectly square, in its original distance.
You can put the seal in without distorting it in any way.
This is where a custom tool comes in handy.
I have a 2006 that I'm currently in the middle of changing the clutch on. Car has approx. 113,000 miles on it. Based on the provided pic of the rear main seal, should I leave it in or replace? Just ask cause of the milage..
Thx
Joined: Nov 2007
Posts: 8,841
Likes: 1,705
From: Illnoise. WAY downtown, jerky.
I bought a 2nd S2000 recently (MY07) for tracking.
No leaks on my input shaft or rear main seal at 164K miles. Including track time.
BUT...I thought I'd be foolish not to do it whilst I was in there replacing the clutch at that many miles.
On my OWN car that I can work on at my own pace.....my habit is to always do them at clutch changes, regardless of miles.
HOWEVER...
I just did a clutch on my friend's MY00 that he just bought for track use as a bullshit, weak minded response to me having the idea first.
His has 60K miles.
I was CONFIDENT in leaving that one alone with the original main seal.
No leaks on my input shaft or rear main seal at 164K miles. Including track time.
BUT...I thought I'd be foolish not to do it whilst I was in there replacing the clutch at that many miles.
On my OWN car that I can work on at my own pace.....my habit is to always do them at clutch changes, regardless of miles.
HOWEVER...
I just did a clutch on my friend's MY00 that he just bought for track use as a bullshit, weak minded response to me having the idea first.
His has 60K miles.
I was CONFIDENT in leaving that one alone with the original main seal.
Last edited by B serious; Sep 13, 2019 at 07:00 PM.