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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Leaking Pinion Seal

  • Thread starter Thread starter JarheadMP
  • Start date Start date Apr 7, 2017

JarheadMP

New Member
Apr 23, 2015
21
0
1
wichita
Apr 7, 2017
#1
  • Apr 7, 2017
  • #1
Okay, anyone else have this and what did you do to fix it?

I had and still have a leaking pinion seal in my 90 LX. I've changed the seal and the nut (me not a shop) and still have a puddle forming when I leave it parked overnight.

The gear set is about a year old and went in with fresh bearings and the works. I noticed shortly after the gear change that the pinion was leaking and informed the person who set up the rear end for me and got a blow off reply. So after having the entire fluid contents end up on my garage floor over winter, I tackled it myself.

Any ideas on what's going on?
 
D

Deleted member 215073

Apr 7, 2017
#2
  • Apr 7, 2017
  • #2
Is the yoke grooved where the seal rides? Was there sealant applied to the splines on the pinion shaft?
 
S

sal5.0

Member
Jul 14, 2007
40
12
18
Apr 8, 2017
#3
  • Apr 8, 2017
  • #3
Pull the pinion flange and check for grooves worn into it. These flanges have a tendency to groove. Replacing the seal will not fix the problem. Replace the flange and seal as a unit. I just did this on my car and now it's bone dry. Here's the link:

https://lmr.com/item/LRS-4851A/86-04-Mustang-Rear-Axle-To-Driveshaft-Pinion-Flange
 
Reactions: Labora and Fordfreak93

Labora

Founding Member
Jun 11, 2000
1,854
26
69
Dallas, Texas
Jan 13, 2019
#4
  • Jan 13, 2019
  • #4
Bumping old post but is any gear setup required if you are just replacing pinion seal? And/or Flange?
 
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