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  • 1996 - 2004 SN95 Mustang -General/Talk-
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Differential Fill Plug

  • Thread starter Thread starter Adverse2Change
  • Start date Start date Jan 10, 2009

Adverse2Change

New Member
Aug 21, 2003
340
0
0
Raleigh, NC
Jan 10, 2009
#1
  • Jan 10, 2009
  • #1
This mother #%(&#$ won't budge. I've tried blaster and other lubricants on it and it will not come loose. Any one have an idea on how I can get this thing loose? My differential needs more oil or it'll rip itself apart.

Thanks
 

MustangLX-5.0

Founding Member
Dec 2, 2000
856
7
38
Lehigh Acres Fla.
Jan 10, 2009
#2
  • Jan 10, 2009
  • #2
You are using a 1/2" drive to access the plug ..right? Has it been removed before? And are you sure it NEEDS oil added to it? Might be best to just pull the cover off and change the oil out alltogether.Clean it up in there while your at it.Inspect the ring and pinion gears.

When you PB the fill plug,make sure you let it soak for awhile.Try agin then spray again.
 

Adverse2Change

New Member
Aug 21, 2003
340
0
0
Raleigh, NC
Jan 11, 2009
#3
  • Jan 11, 2009
  • #3
Yes I am using a 1/2" drive. No one has ever touched back there. My initial plan was to check the level, and then remove the housing and replace all of the fluid, but if I can't access the fill plug then there is no way to do that!

I took it to a shop on saturday, test drove it with a mechanic, and he figures that my bearings may be going out... and since he's planning on basically dismantling most of the rear end I'm going to have him price some new gears for me.

We'll see what happens.... gonna be some serious $$$$$.
 

Skymarshal

Member
Nov 5, 2004
572
0
16
Dallas
Jan 11, 2009
#4
  • Jan 11, 2009
  • #4
Junkyard 8.8" rear end off a GT. Get everything you want all at once...
 

Adverse2Change

New Member
Aug 21, 2003
340
0
0
Raleigh, NC
Jan 11, 2009
#5
  • Jan 11, 2009
  • #5
Is it absolutely necessary to go with an 8.8" rear if you want to go to 373s? I can understand going to a beefier setup if you are really going to be adding some major power, but what if you aren't?
 

Skymarshal

Member
Nov 5, 2004
572
0
16
Dallas
Jan 12, 2009
#6
  • Jan 12, 2009
  • #6
No- you can put 3.73s in your 7.5" rear end. I was just thinking it might be easier since you have an unknown noise and you want to do gears anyway. Putting in the 8.8" would give you a limited slip too, which would be nice even if you don't have a power adder.
 

Adverse2Change

New Member
Aug 21, 2003
340
0
0
Raleigh, NC
Jan 12, 2009
#7
  • Jan 12, 2009
  • #7
I'm getting a good price on 3.73s with a locker in the stock housing...

my bearings on the other hand....:fairyfight:
 

MustangLX-5.0

Founding Member
Dec 2, 2000
856
7
38
Lehigh Acres Fla.
Jan 12, 2009
#8
  • Jan 12, 2009
  • #8
Adverse2Change said:
I'm getting a good price on 3.73s with a locker in the stock housing...

my bearings on the other hand....:fairyfight:
Click to expand...

Rear axle bearing kit with shims will run you $70 - $90.But that's for an 8.8 .Not sure about 7.5. It had cost me $90 for the 8.8 kit from Ford...and I work here (dealership).

I wonder if you can just use an impact wrench on that plug? Hmm.Can't think of anything else if it wont budge.Sounds like you live up north and the gear oil has never been changed out of it.
 
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