Gt04

Check your tire wear, find a nice even pavement area to see if it was just the road. Still one try new fluids if that don't work go ahead and replace the clutch packs and might as well do some gears while its apart. Mine went at about that mileage.

rastarocket

ok ok that sounds like a good idea, im gettin the pinion seal replaced next week, and ill just have them change the oil, i know you gotta at the extra friction modifier, but what do you think of the royal purple that has it already in it?

http://www.americanmuscle.com/royalp...0-gearoil.html

or is it better to get a diff oil and add the friction modifier my self?

rastarocket

can you tell me more about this clutch pack?? a link or something? id appreciate it alot.

cliffyk

Personally I would not use synthetic oil in a rear-end as most are too slippery already to let a clutch type LSD work agressively--also most do not need any additional f/m--check with the manufacturer's website, email or call them to make sure.

OTH, with dino oil you get to decide how much f/m gets added. Ford's recommendation is 4 oz, use less for a more aggressive LSD--personally I find 4 oz, and most synthetic oils with no f/m, to be too slippery.

FWIW, I run Valvoline 75W-140 dino juice with 3 oz or f/m...

69MustangCoupe393cid

I have Amsoil Synthetic in mine. Had it in since 60k miles or so and the car now has over 80k with original clutches. I didn't add any friction modifier and it works perfect. From a stop both tires will spin, but in a turn it will allow the diff to work the way it should unless you push it, then yes things can get hairy if you do. A lot of LSD's come with synthetic from the factory, so in my opinion, no reason to be scared of a good synthetic.