Pinion Seal

[CARdiac]

Have any of yooz gyz ever replaced the rear pinion seal (the seal into the dif from the driveshaft)? How hard is it?

[BLLDOGG]

dude, you need to search on this one. its just as common as a rear main leak

[CARdiac]

Sorry, newbie type error...

It seems common, I have grime sprayed around the rear dif but no drips....should I even bother?

[BLLDOGG]

well im not sure on the fixing price but if you do it yourself and dont have the tools, it will be expensive. i was going to fix mine for the hell of it but i dont have the torque wrenches and they are ****ing expensive. if its not dripping, dont worry about it. just check you fluid if you can. i dont know if there is a dip stick or what. im stupid [img]graemlins/twak.gif[/img]

[hawgs]

No real way to check the fluid unless you add more and see what happens. There is a fill hole on the side of it and the fluid level should be pretty close to that. So you could add some until it overflows and then you will know it’s full.

The pinion seal is not hard to get to at all... however you have to pull the carrier out then pull the pinion out and replace the seal. When you pull the pinion out you will mess up the backlash (how far out the pinion sits so that it makes proper contact with the ring) when you put it back in. This is the only part that keeps most people from installing their own gears and forces people to take it to a professional to do... because it has to be extremely accurate otherwise it will lock up or make horrid noises.

So in short... take it to a shop and let a pro do it. It's not that it is a hard job; it is just that precision is extremely important... and that’s hard to do unless you’re trained with the different measuring devices and such to get the backlash set just right.

[BLLDOGG]

yep, like i said, expensive tools are needed. i fifgured i would just take mine to the dealer since who better to do precision stuff like that then them

[CARdiac]

So what i am getting from this.....sine I'm not leaving oil droplets on my garage floor and my level stays fairly good btw changes (will know next week when I do my DS and change the fluid) I should just leave it alone!

[BLLDOGG]

yeah

[chas]

Originally posted by hawgs:
The pinion seal is not hard to get to at all... however you have to pull the carrier out then pull the pinion out and replace the seal. When you pull the pinion out you will mess up the backlash (how far out the pinion sits so that it makes proper contact with the ring) when you put it back in.

this is the 'hard' way. the haynes manual (and the gm/helms repair manual as well i believe) have a different procedure. the short version is:

just up rear end with the wheels free to rotate

mark orientation of companion/pinion flange and the pinion nuts and the driveshaft

disconnect driveshaft

using a torque wrench/gauge (in/lbs) measure the force needed to rotate the wheels (this is the bearing preload which you need to restore at the end of assembly)

remove pinion nut and companion flange (you will need a puller for the flange -- you cant pry on it or damage may result)

now replace the seal (be sure to lubricate the lips of the new seal or this exercise will be pointless)

install companion flange and pinion nut making sure to get the alignment marks made earlier lined up.

now at this point you need to measure the force required to turn the wheels. you need to make this force 10-12 in/lbs more than the earlier recorded value to account for the drag from the new seal. this will restore the previous bearing preload. do not loosen the pinion nut! there is a crush sleeve between the pinion bearings and it only compresses. just tighten in small increments and keep measuring. i tightened about 1/3 of a turn more than my previous marks.

[chas]

be sure to put gasket sealer on the pinion splines that go ito the companion flange and behind the pinion nut washer prevent leaking.

i think not a few people get leaking since the sealer gm uses seems to turn hard and crumbles.