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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Leaking Gear Fluid at Rear Wheel

  • Thread starter Thread starter fasttback
  • Start date Start date Oct 15, 2007

fasttback

New Member
Apr 16, 2005
471
0
0
Northern CA
Oct 15, 2007
#1
  • Oct 15, 2007
  • #1
It looks like gear oil is getting pass the axle seal in the 9” big bearing rear end (both sides), but only leaking on one. Is it normal to have gear oil leak pass the axle seal and get stopped by the flange seal? Both axle seals are new and the axle surface shows no grove in it.

When pulling the axles, I don’t recall having oil in the sealed bearing area before.
 

CraigMBA

New Member
Mar 24, 2007
783
1
0
Orange, CA
Oct 15, 2007
#2
  • Oct 15, 2007
  • #2
It should be dry.

Are you sure you've got the right seals for your axles?
 

fasttback

New Member
Apr 16, 2005
471
0
0
Northern CA
Oct 15, 2007
#3
  • Oct 15, 2007
  • #3
CraigMBA said:
It should be dry.

Are you sure you've got the right seals for your axles?
Click to expand...

That's what I'm starting to question myself. The PO bought new seals and bearings for the housing, I just had them installed by a driveline shop. I could measure the seals vs the axles, but I'm unsure of how much "undersize" a seal has to be for a given size axle?
 

ultrastang

Founding Member
Feb 26, 2002
1,092
2
37
Arkansas
Oct 15, 2007
#4
  • Oct 15, 2007
  • #4
A new seal can leak soon after installation if the weight of the axle was dragged across the neoprene portion of the seal, which would put small knicks in it.

If the seals have recently been installed, you sould be able to easily see the part numbers on them (if they are the correct seals), for ease of buying replacement parts.

I have a list of replacement parts on my site in this link, if you scroll down the page: http://ultrastang.com/Rearinfo.asp?Page_ID=16
 

fasttback

New Member
Apr 16, 2005
471
0
0
Northern CA
Oct 15, 2007
#5
  • Oct 15, 2007
  • #5
ultrastang said:
A new seal can leak soon after installation if the weight of the axle was dragged across the neoprene portion of the seal, which would put small knicks in it.

If the seals have recently been installed, you sould be able to easily see the part numbers on them (if they are the correct seals), for ease of buying replacement parts.

I have a list of replacement parts on my site in this link, if you scroll down the page: http://ultrastang.com/Rearinfo.asp?Page_ID=16
Click to expand...

Nice site Ultrastang! Found this matching my rearend:

1957-1959 STATION WAGON/RANCHERO 9-INCH (Large Axle Bearing Housing)

2. Axle Seals: p/n 51098 (2 req.).

It might be hard to read the part number because the driveline shop used silicone around the base of the seal and housing tube. I will give it a shot tonight.
 

ultrastang

Founding Member
Feb 26, 2002
1,092
2
37
Arkansas
Oct 15, 2007
#6
  • Oct 15, 2007
  • #6
fasttback said:
Nice site Ultrastang! Found this matching my rearend:

1957-1959 STATION WAGON/RANCHERO 9-INCH (Large Axle Bearing Housing)

2. Axle Seals: p/n 51098 (2 req.).

It might be hard to read the part number because the driveline shop used silicone around the base of the seal and housing tube. I will give it a shot tonight.
Click to expand...

Thanks.

I hope that this wil remedy your axle housing's leaking problem.
 
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