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Has anyone ever installed a rear main seal with any success (no leaks)?

  • Thread starter Thread starter yellowstang1994
  • Start date Start date Feb 3, 2007

yellowstang1994

New Member
Sep 9, 2004
338
0
0
Feb 3, 2007
#1
  • Feb 3, 2007
  • #1
Guys, this is ridiculous. The time is coming for some new parts in the drivetrain. I'm on my 3rd rear main seal right now and it's leaking worse then I've ever seen yet. I've taken every step mentioned on any guide, or instructions to install a rear main seal with proper sealants etc... I came to the fact that theres always going to be a leak no matter what. But I'm wondering has anyone ever installed one and not had it leak (say a year later?). I'm questioning the teflon seals I'm using. Everyone lives by them but why are teflon seals so superior to rubber seals? So teflon can stop a bullet from going through your chest, but do they seal any better over rubber? And how so? I'm just not seeing why?

Anyway, if you installed one of these seals with out any problems of leaking down the road, please let me know exactly what you did, and what you used. Thanks!
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
18
108
Chicagoland
Feb 3, 2007
#2
  • Feb 3, 2007
  • #2
I've always gone the cheap route and replaced them with rubber ones when doing my clutch. Does yours leak immediately after replacing the seal? It may have worn a groove in the crank and require a sleeve to permanently repair it now.
 

trav_19

New Member
Oct 29, 2006
810
0
0
Jackson, MI
Feb 3, 2007
#3
  • Feb 3, 2007
  • #3
i had a rear main put in my 93 about 4 years ago never leaked a drop since...? i had it put in by a ase certified mechanic...?
 

parchisi

New Member
Apr 13, 2006
519
1
0
New Mexico
Feb 3, 2007
#4
  • Feb 3, 2007
  • #4
Mine leaks and its rubber on a brand new crank. I dunno, I'm just gonna live with it. oh, and teflon is what they use to make non-stick frying pans. Kevlar is what stops bullets.
 
W

wytstang

Mustang Master
Mar 14, 2004
4,988
4
78
Summerville,SC missing South Fl. weather :(
Feb 3, 2007
#5
  • Feb 3, 2007
  • #5
I learned to live with mine, I'm on my 2nd or 3rd. I put a crank sleeve on the last one and it still leaks.
 

trav_19

New Member
Oct 29, 2006
810
0
0
Jackson, MI
Feb 3, 2007
#6
  • Feb 3, 2007
  • #6
hummmm now you guys got me scared lol...my 94 needs one haha seems like the 94-95 cars seem to have a problem back there...

oh btw on the kevlar to teflon comparrison lol haha
 

yellowstang1994

New Member
Sep 9, 2004
338
0
0
Feb 3, 2007
#7
  • Feb 3, 2007
  • #7
hmm, i'll read into the sleeve, when I get ready to do it again. Mine doesn't leak immediatley after I put in the seal (at least that I can notice). But in about a month it will.

lol, i just realized now about the kevlar. I was reading about teflon earlier and they said they use it to make armor piercing bullets, so when I wrote it I guess I had bullet proof vests on my mind, haha.

Any other ideas? I noticed there are lots of different recommendations on what sealants to use on the seal? Just trying to find out the best way, and what works.
 

OrangeMustangGt

Founding Member
Mar 7, 2002
1,976
0
36
Cape Cod, MA
Feb 3, 2007
#8
  • Feb 3, 2007
  • #8
i replaced one, and it leaked more. Turned out the sping in side slipped off. If your careful it wont leak
 

vp6799

New Member
Aug 15, 2006
124
0
0
Massachusetts
Feb 3, 2007
#9
  • Feb 3, 2007
  • #9
I replaced mine when I did the aode to T5 swap. I used a small amount of silicone sealer on each side of the seal. I've always done this to everyone that I do. Never had one leak once it was replaced.
 

diablostang

New Member
Sep 21, 2004
425
0
0
Raleigh, NC
Feb 3, 2007
#10
  • Feb 3, 2007
  • #10
Never had one I replaced leak on me...
 

RIO5.0

15 Year Member
Feb 16, 2001
6,892
8
128
N.H.
Feb 3, 2007
#11
  • Feb 3, 2007
  • #11
I replaced mine 10k ago and its leak-free to date....Its the one the came in the FRPP full gasket kit....No silicone or nada....It did have the Teflon coating on the O.D. Long as no scoring is apparant on the crank journal you should be good to go...Maybe you have an issue in the PCV system??? and the oil's finding the easiest way out??

I think I'd be some pissed after 3 times...
 
W

wytstang

Mustang Master
Mar 14, 2004
4,988
4
78
Summerville,SC missing South Fl. weather :(
Feb 3, 2007
#12
  • Feb 3, 2007
  • #12
I was but whacha gonna due , next time the tranny comes out I'm going to have the shop slather it down with liquid nail.........o.k not liquid nails but somthing it's getting kinda old. I need a quart every 4,000 miles (ball park) if i go on a 5+ hour trip is when it needs some during the long haul.
 

NotQuik

Founding Member
Oct 21, 2000
5,158
29
88
Central Florida
Feb 3, 2007
#13
  • Feb 3, 2007
  • #13
don't feel bad i'm in the same boat...replaced it while i did the 5 speed swap with a regular one and it leaked...tried a teflon one and it leaks....i'm going to sleeve it next time i guess.
 

94-302-vert

Active Member
Aug 16, 2004
1,947
2
36
NE CT
Feb 5, 2007
#14
  • Feb 5, 2007
  • #14
Yeah, i am pulling my trans in the coming weeks too, for the same reason.. I put 10k without a drop on this seal and then all of a sudden it is basically puring fluid...
 

gcomfx.com

Founding Member
Oct 22, 2002
3,690
0
56
Republic, MO
Feb 5, 2007
#15
  • Feb 5, 2007
  • #15
My original one started leaking around 180k.... I'm swapping the engine. Hope that fixes it.
 

Killercanary

The car that set the bar.
Founding Member
Nov 29, 1999
5,676
1
76
Altoona, PA
Feb 5, 2007
#16
  • Feb 5, 2007
  • #16
What is this sleeve that you all are refering to? I've replaced mine 3 times on my car so far, but I basically do it everytime I put a new clutch in.
 

trav_19

New Member
Oct 29, 2006
810
0
0
Jackson, MI
Feb 5, 2007
#17
  • Feb 5, 2007
  • #17
Killercanary said:
What is this sleeve that you all are refering to? I've replaced mine 3 times on my car so far, but I basically do it everytime I put a new clutch in.
Click to expand...

ouch you must be hard on it lol
 

WhiteDevil

New Member
Feb 4, 2003
2,717
0
0
San Diego
Feb 5, 2007
#18
  • Feb 5, 2007
  • #18
I replaced my leaky one on my old 302 and it still leaked. My shortblock builder put one in on my new 347 and this one also leaks. Not terible but still after sitting over night there i usually a drop or two. Lame!
 

Yobi1Kanobi

Member
Apr 9, 2003
559
0
16
Feb 5, 2007
#19
  • Feb 5, 2007
  • #19
no luck here...but then again i could never tell cuz my dip stick was popping off and leaking,my oil pan,valve cover ,and breather.
 
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