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Leaky rear main seal on the 89 Saleen

  • Thread starter Thread starter deathsled
  • Start date Start date Apr 21, 2013

deathsled

Member
Mar 20, 2013
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4
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63
Chicagoland
www.treadheart.com
Apr 21, 2013
#1
  • Apr 21, 2013
  • #1
I saw some oil on the garage floor and suspect that the rear main seal is leaking more so needs replacement. I've done some things on cars myself like replacing a water pump or radiator on an 86 Towncar but have never dropped a transmission. How hard is it to replace a rear main seal on these cars? I don't have a lift in my garage but I am in the "I think I can, I think I can" mentality right now. Am I gettin' in over my head? I suspect I might have to replace the clutch disk too because there is a little slippage that is intermittent which might mean oil on it from the leak? Also saw some antifeeze on the floor. The rad is original to the car? Rad going bad too?
Opinions?

Thanks,

Richard E.
 

MikeH686

Mine is only two inches though.
10 Year Member
Oct 11, 2011
2,843
1,753
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35
Waldorf, MD
Apr 21, 2013
#2
  • Apr 21, 2013
  • #2
Aod or t5? Do you have 4 jackstands
 

deathsled

Member
Mar 20, 2013
36
4
9
63
Chicagoland
www.treadheart.com
Apr 21, 2013
#3
  • Apr 21, 2013
  • #3
T5 and only two jackstands. It isn't hard to get two more. Just wondering if there is enough room underneath to work. Plus I don't know the proper torque settings if I am to reinstall etc. I could use the hydraulic jack to lower the transmission or buy something made to lower transmissions.
 

boostfrk

10 Year Member
Aug 30, 2011
712
69
59
Colorado
Apr 21, 2013
#4
  • Apr 21, 2013
  • #4
It can be done and it's not too hard. If you can get the car up high enough with a good hydraulic jack and securely support it with 4 jackstands then you'll have enough room.

Quick & dirty steps...
Drop the h-pipe
Remove driveshaft
Remove interior console/shifter
Drop the trans
Remove clutch fork and bellhousing
Remove pressure plate/clutch
Remove flywheel
Then you can get to the RMS

While you have it all apart you might as well replace the pilot bearing, flywheel, clutch kit, throwout bearing (Ford OEM) so you don't have to go back in.

I just did all of this last month. You can see some pics here on page 11 http://www.stangnet.com/mustang-forums/threads/1990-lx-5-0-restomod-build.860098/page-11
 

HuskerNation

Member
Nov 4, 2011
252
16
19
West Des Moines, IA/Omaha, NE
Apr 22, 2013
#5
  • Apr 22, 2013
  • #5
Its not difficult at all! Don't let all the write ups intimidate you. I did my first one in January, and it went way better than I expected. Use white lithium grease to put the rear main seal back in, its the easiest way, and insures you won't ruin it putting it back in, if you evenly hit it back in place.

When you get to the rear main seal, just use your regular tools you have in your garage to get it out. I tried the screw method, and it laughed in my face. There is a much easier, and safer way (if you are patient). Take a flat head screwdriver, and bend the outside of the rear main seal towards the center. You have to be careful, and make sure you don't slip and hit the crank. Light careful taps will ensure this. When you do this, you will create a gap where you can up the end of the screwdriver between that, and the outer metal, and pry it out. This doesn't take much force at all, and it comes out with ease.



What I did to get the new one in, I used white lithium grease and coated the new seal. I then put it where it needed to go, and used the old seal to help guide it in. Instead of tapping the new seal, I tapped the old one, and used it as a protector and guide, if you know what I mean. This also made the seal sit all the way in.

I did mine by myself for the most part, with 4 jack stands and a jack. If you have an extra hand, it should be easier.
 

deathsled

Member
Mar 20, 2013
36
4
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63
Chicagoland
www.treadheart.com
Apr 28, 2013
#6
  • Apr 28, 2013
  • #6
Thank you very much for the tips. I have heard that the old seal causes wear on the crank and actually the wear into the crank from years and millions of revolutions causes even the new seals to leak. Is that true? The leak is not horrible but I am still considering swapping it out for a new seal.
 

boostfrk

10 Year Member
Aug 30, 2011
712
69
59
Colorado
Apr 28, 2013
#7
  • Apr 28, 2013
  • #7
Seems like it's kind of hit and miss. Some people experience a leaky seal after they replace it and others don't. I only have 25 miles on mine since I replaced the seal, and I also switched back to 10W-30 weight oil, so it's too early to tell.
 

HuskerNation

Member
Nov 4, 2011
252
16
19
West Des Moines, IA/Omaha, NE
Apr 29, 2013
#8
  • Apr 29, 2013
  • #8
In my opinion, where people run into issues, is the actual installation itself. If you force it on, your going to cause weak points in a seal. This is why lithium grease comes into hand, and a light even tap to make sure your not putting too much pressure on one side. You always want to check for burs or sharp edges before you put it back on. I didn't have any, but mine was original. 150K miles and it just started to leak.
 

Gearhead92

Member
May 23, 2012
153
6
19
Baltimore area, Maryland
Apr 29, 2013
#9
  • Apr 29, 2013
  • #9
Mine is also leaking, and I'm just buying some time before I have to put work into the trans. I bought a slightly used Centerforce (500 miles give or take) and the guy threw in a freshly turned stock flywheel.

Now, I am a novice at this point, I've only done minor work, the most complicated of which was front A arms and springs to date.
It seems like I have the equipment, no problem, but is this really not that bad? I have a feeling Murphy has other plans in store for me if I tackle this one in my driveway.

The A arms where a pain as well, because of my lack of knowledge.

And what is a bad leak? I used to have to put a quart in every month maybe a month and a week. That has slowed down a bit, after I put one of those oil system anti-leak things in. Just thought I'd try it out. It has seems to slow the leak down, but I still need to replace the seal.
 
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