changing differential oil

[Ifixyawata]

Scott's got it right. The only Fox Chassis T-birds or Cougars that ever got an 8.8 from the factory were the '87 and '88 TurboCoupes and the '88 Cougar XR7. All others were measly 7.5's.

[Freshmeat]

And gear oil is one rank smell.

I've actually developed an appreciation for the smell.

Then again, I've had a few too many and called a really good friend of four years by teh wrong name...

[monterey1962]

This is a 2.73 open rear.

[Lincolnmania]

FYI, all 5.0L come with 8.8 rears. And gear oil is one rank smell.

nope the mustang did not get the 8.8 till the mid 80's seen tons of fox chasis v8 cars with a 7.5" rear

[Blaze86Vic]

FYI, all 5.0L come with 8.8 rears. And gear oil is one rank smell.

[Lincolnmania]

it's either a 8.8 or a 7.5 rear changing the oil is the same
use some 80w90 and trac lock additive if it has one..........get some carb cleaner too........spray out the sludge while you have the cover off........it takes just over 2 qts of gear oil to fill it up, teh fill plug is on the front side of the unit on the ds next to the pinion flange.........get ready to smell one of the worst smells on teh planet lol
scott

[Blaze86Vic]

Yes it is an 8.8 rear. Motorcraft gear oil is what's in mine. I forget which weight though, I keep thinkin 90 weight for some reason though.

[monterey1962]

This is regarding the '87 Cougar. I noticed a bit of a mess on the bottom of the diff. today. I was thinking of putting a new gasket on. It probably needs fresh oil, as well.

What oil should I use? How much? Should I use some Lucas treatment? Any tips or info is appreciated. I'm assuming it's an 8.8 rear end.