Pinion Seal

[69BirdX]

My Pionion seal is leaking and its a little more then a couple drops. I ust bought the car it has a 12 bolt moser with 3.73s. The rear cant have more the 3k on it. So im just gonna replace the seal and advice or precautions i should know. What kind of seal do i need? Also should i replace my driveshaft with a alumium while i doing this job. Is it worth the money.
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Box Vaporizers

[WildBillyT]

This is another great writeup on pinion seal replacement, I have done a few this way and it works well.

GM says to use a new nut, but you don't have to. Don't change the crush sleeve, either.
If you use the same nut then mark it at 12:00 position with a punch and your new setting will be a tad past that. I needed to use an impact gun to undo the nut.

-jack the car up off the rear wheels
-remove the rear tires
-use a inch lb torque wrench and measure the torque it takes to turn the axle, this will be the reading you'll need when the nut is tightened to where it was before you started, but add 1-2 in lb to make up for the extra drag on the new seal.
-remove nut
-clean threads
-pack seal cavity with wheel bearing grease
-lube the seal rubber part with oil so it doesn't tear
-the manual says to use permatex II sealant on the threads, some use loctite
-screw nut on and tighten down in increments and take your torque reading and get the correct drag + 1-2 in lb.
-you'll need to put the wheels on and lower the car to tighten the nut unless you rig up a tool to screw on the yoke so it touches the ground and stops the axle from turning. So if you want you could take your in lb reading with the wheels on so your not taking them off and on so many times.
-if you had a small small leak dripping you'll still have a smaller one still even though you have a new seal because the old seal made a grove on the yoke from turning for years while you drive.

[69BirdX]

Thanks for the advice and the know how to do it that really helps. This is for my 98 trans am so now i need to know if an aluminum drive shaft is worth my money and what kind of seal should i buy?
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I pen vaporizer

[alamantia]

sometimes the cause of a leaky pinion seal is because the spring on the back of it breaks, when you pry the old one out make sure the spring is on there, if not, fish it out of the rear, make sure to clean the yoke up with a scotch brite and lube the inside of the new seal so it dont burn out, put the driveshaft back in the same orentation as it came out, mark the u-joint and yoke and pinion splines with a crayon

[johnjzjz]

great help on the seal --- yet another way to aid in seal retention is to fill the back of the seal ( the cavity ) with silicone -- allow 24 hours to dry before use - by doing so the seal lip has a much tighter hold and spring stays put - on the shaft or yoke in this case its a real fix for a front motor balancer when a sleeve repair is not available and the grove that has worn into it is deep, its like starting all over again - i can picture one done i keep them in stock for such a job mostly trans front seals -- jz