I'm working on a 71 Cutlass with an 8.5" rear. The pinion seal is leaking like mad, and the guy wants it fixed. I've seen my boss do it with an impact until he "feels" it has the proper amount of tension. I don't think that really the right way to pre load the pinion. IS there a trick to this? I have a torque wrench, but it is not the best. Any ideas, or tips? thanks..
There's a proper way for everything, but some people get lucky and get away with the improper way. A new nut and crush sleeve (which will require that impact or muscles) should be used when replacing a seal. About 5-10 in/lbs of preload on those used bearings after the sleeve is crushed down to where the bearings are just contacting the inner and outer races. Honestly there is usually more to it than just the seal has gone bad. About 9 out of 10 diffs I have been asked about just putting a seal in have needed more work. The bearings / races are usually worn in some way. Depends on mileage, previous use, and more. Sometimes its the end yoke that is grooved. I guess it really depends on your knowledge and how far you're willing to go to repair it. My opinion but I think Jim and Roger would concur. Tim
What Ive done in the past is to mark the pinion and the nut. Once the new seal is installed, tighten down the nut until the marks line up again. This way the crush collar doesnt get disturbed. There is a possibility that the rubber is dried out or cracked. That was the case in my situation.
I was thinking something like that too. I was going to count the turns and snug back in. I'm not about to tear into this rear laying on my back, in my driveway..
My way... Well, here is what I did. I used a decent torque wrench when taking the nut OFF. Then I replaced the seal, and torqued the nut back on to the same value. This worked fine.
pinion seal buzz it off with the impact. remove yoke, remove the seal. clean area. put sealent around the perimeter of the outside of the seal outside diameter. tap new seal in carefully. grease up the rubber seal and the yoke where they will meet. insert yoke. lock tight the nut threads. replace nut at tight as you can with just your own arm strength. ( you will not be able to crush the sleeve by hand) unless you really really work out...lol) over 125 ft lbs of torque needed to do this and you most likely will not get that from a 1/2 wrench with one hand. Then if you reallwant to make sure the nut does not back off punch the nut on each side toward the top of the nut. Your done. This is if everything was OK to begin with...to spec. Good luck, Jim J D Race
Well I R&R the seal this weekend. I buzzed it off with an impact, qnd tightened it by hand. I felt it hit the crush seal and I went slightly more, about an 1/8 turn. no problems, no leaks.
crush sleeve Well if it was dne right in the first place it really should not be felt. the bearing and crush sleeve will kind of work at the same time and stop. If the crush sleeve was crushed too much the pinion would be hard to turn. Bad will burn up the bearings. If the crush sleeve was not crushed enough the bearing would be too lose creating a lose pinion and the ring gear and pinion teeth will suffer from the slop. Sounds like your going to be fine. Good luck and have fun. Jim
