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Rear end questions on '98 Cobra

  • Thread starter Thread starter fastlane65
  • Start date Start date Apr 20, 2007
F

fastlane65

New Member
Dec 1, 2004
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North Louisiana
Apr 20, 2007
#1
  • Apr 20, 2007
  • #1
I've never had anything to do with an 8.8 rear end before. I bought a '98 Cobra Wednesday afternoon, and was checking everything out last night. I pulled the fill plug out of the carrier and the end was covered with what looked like gray putty. It had a graphite feel and smelled really bad. Diff was full and what seeped out was really thick and same gray color. Definitely not the Royal Purple I use in my classics.

The car only has 24,800 miles and gets good traction to both wheels, but there is a noise coming from the back that reminds me of our washing machine. My first guess would be a bearing, but the gray ooze has me worried. I plan to pull the back cover and inspect this weekend. I would have done it last night but it was late and I figured I better have a new gasket on hand for the cover.

Any good links with pictures on how to inspect/rebuild an 8.8? All other suggestions always welcome.
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
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Apr 20, 2007
#2
  • Apr 20, 2007
  • #2
Everything you observed is perfectly normal (except for the washing machine noise).

If you want some peace of mind though feel free to change the diff fluid.

There is no gasket for the cover, use RTV.
 
F

fastlane65

New Member
Dec 1, 2004
14
0
1
North Louisiana
Apr 20, 2007
#3
  • Apr 20, 2007
  • #3
Thanks for the peace of mind. What did the factory fill these with? It brought back fond memories of changing diapers.....
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
4,749
95
134
Apr 20, 2007
#4
  • Apr 20, 2007
  • #4
I believe yours is filled with 80W-90 gear oil.
 
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