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8-3/4 Pinion Seal replacement question.

lochenjons

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Leaky pinion seal on a 742 case 8-3/4. Got the seal at home. Do I have to replace the shims when I replace the seal? Or does it depend on the thickness of the seal? Sorry for the noob question... never done a pinion seal. I got the service manual for my car at home but I won't be back until Friday... trying to order parts if I need to sooner than later. Thanks
 
No need to do anything but re torque pinion nut to factory specs.
 
you need to take a punch and mark the nut and the pinion, you take it off so you can reposition it a hair further.
so you keep the preload on the sleeve inside. when you have the flange off , I suggest to inspect it for wear.
they do make a thin sleeve that you can buy to press onto the flange so seal will rest on that instead of grooved flange
 
I just did one on a jag . like this

IMG_7904.PNG
 
you need to take a punch and mark the nut and the pinion, you take it off so you can reposition it a hair further.
so you keep the preload on the sleeve inside. when you have the flange off , I suggest to inspect it for wear.
they do make a thin sleeve that you can buy to press onto the flange so seal will rest on that instead of grooved flange

If the pig was a 489 (with a crush sleeve) I like to add a .010" shim on the small end of the sleeve and crush the sleeve another .010" to achieve the correct pinion bearing preload with out extra disassembly. Since this question pertains to a 742 the #2 response is correct.
Mike
 
Will do thanks, Before I really knew what I was doing I tried to impact the nut off. So I’m pretty sure it’s not where it’s supposed to be so I probably can’t mark it
 
Will do thanks, Before I really knew what I was doing I tried to impact the nut off. So I’m pretty sure it’s not where it’s supposed to be so I probably can’t mark it

On a 742 you don't need to mark it. Just torque it to specs. The factory service manual says 240 ft lbs. Try to get it close to that.
 
Will do, got the rear diff in yesterday, she's slowly coming together. thanks for your replies guys
IMG-3919.jpg
 
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