Exactly how the hell am I supposed to torque down my pinion nut?

[BuickMike]

After driving the GN around the block a few times I noticed a whining noise coming from the rear end. My pinion seal is also leaking. I initially though the noise was from the backlash being too much, but I was pretty confident that I set that correctly when I put in all new bearings and seals awhile back. I will be pulling the rear end apart tonight, but I'm assuming the noise is from the pinion bearing now.

I did my best to use a in-lb torque wrench to tighten the pinion nut until I would get it to click at 25 in-lbs when I turned the pinion nut while the ring gear was out. I was trying to measure resistance of course. I thought that was what I was supposed to do, but at this point I'm guessing that the pinion nut is too loose and the pinion is walking around.

Also, the replacesment crush sleeve was a larger diameter than the original. Is that correct, or do I have the wrong one in there?

HELP!!!

 

[turbofabricator]

If you still have the old crush sleeve, slide it over a tube of proper diameter and hammer the "bulge" a little to lengthen the sleeve. Crushing the sleeve is a PAIN to do correctly. Easiest way is with a 350 ft/lb impact gun. A dial type torque wrench is best to set the drag. Hammering the old crush sleeve out is an "Old Timers" trick showed me 25 years ago.

 

[Race Jace]

It sounds like you did it correctly. If you pinion seal is leaking and it the pinion is now loose check for the wire rings coming out of the seal. We did one and somehow the tension wire got between the yoke and the bearing when we set everything up and then it worked its way free in service causing the bearing set to be loose. it did the exact same thing you are describing.

did it whine from the get go or did it start whining?

 

[Chuck Leeper]

Use a "crush sleeve" that has shims in it, and do away w/ the high torque required to crush the old design.
Take a used pinion nut, chuck it up and turn the locking part off. Assemble w/ the adj sleeve, and a couple shims. Snug the nut, check the rotating torque. Add/remove shims as required.

look at Summit for them. I think RATECH makes them. They are a solid, 2 pc design that has a recessed area in the outer cup, for the shims.

 

[BuickMike]

It sounds like you did it correctly. If you pinion seal is leaking and it the pinion is now loose check for the wire rings coming out of the seal. We did one and somehow the tension wire got between the yoke and the bearing when we set everything up and then it worked its way free in service causing the bearing set to be loose. it did the exact same thing you are describing.

did it whine from the get go or did it start whining?

It was whining right off the bat. Is that what happened to you?

 

[BuickMike]

If you still have the old crush sleeve, slide it over a tube of proper diameter and hammer the "bulge" a little to lengthen the sleeve. Crushing the sleeve is a PAIN to do correctly. Easiest way is with a 350 ft/lb impact gun. A dial type torque wrench is best to set the drag. Hammering the old crush sleeve out is an "Old Timers" trick showed me 25 years ago.

I have the old sleeve. Here's the question though. After I use a impact to get the sleeve crushed, then what do I do to set the proper drag, back off te bolt??

 

[timdesu2000]

You have to sneak up on the preload. Tighten the nut a little at a time and keep checking the turning torque required untill you get it in spec. If you go too much then you will have to take it apart and replace the crush sleeve or as someone suggested try to reform your sleeve then start all over again. Once the sleeve starts to crush it takes very little turning of the pinion nut to increase preload.

 

[BuickMike]

That's pretty much what I did. Looks like this is just a simple case of me getting the incorrect crush sleeve.

 

[BuickMike]

Update: I pulled it apart and the pinion was a bit wobbly. Looks like I hit the load on the front bearing before the crush sleeve crushed. After draining the gear oil I did find some tiny gold metal dust at the bottom. So far I have absolutely no clue where it came from. I inspected the carrier, front, and rear pinion bearings and they all look fine. The ring and pinion look fine too. Keep in mind I only drove maybe 1 mile max like this. I looked at every single roller on every bearing and saw nothing. All races look perfect too. At this point I think that the front pinion bearing would have taken 95% of the abuse so I may just replace that one to be safe.

So looking back I guess I should have found it odd that I didn't have to torque the crap out of the pinion nut to get the correct preload. I've only done one rear end before this one and it was about 15 years ago. I just took an impact wrench to the pinion nut until the pinion had a slight bit of resistance, just like as if I was doing a front wheel bearing. I did the math on the shims and eyeballed the backlash haha. That rear end got thousands of miles put on it and is still working perfect today lol.

 

[hiboom]

torque

from every thing I've read and all the people I've talked to that do this type of work for a living you can not use a click style inch lb. torque wrench to set pinion drag if using the crush collar.will not give you proper reading .Of coarse I didn't ask until I'm going thought the exact same thing as you.

 

[XXQUICK6XX]

After driving the GN around the block a few times I noticed a whining noise coming from the rear end. My pinion seal is also leaking. I initially though the noise was from the backlash being too much, but I was pretty confident that I set that correctly when I put in all new bearings and seals awhile back. I will be pulling the rear end apart tonight, but I'm assuming the noise is from the pinion bearing now.

I did my best to use a in-lb torque wrench to tighten the pinion nut until I would get it to click at 25 in-lbs when I turned the pinion nut while the ring gear was out. I was trying to measure resistance of course. I thought that was what I was supposed to do, but at this point I'm guessing that the pinion nut is too loose and the pinion is walking around.

Also, the replacesment crush sleeve was a larger diameter than the original. Is that correct, or do I have the wrong one in there?

HELP!!!

The inch pound reading is the amount of force it takes to turn the pinion wheels in the air and no drag on the brakes. Not the torque of the pinion nut, IMO i would have took the old crush sleeve and mic. it and crushed it to the same thickness as the original so you get the proper gear mesh the inch pound reading is just for amount of force it takes to rotate the yolk.

 

[BuickMike]

I understand that the in lb reading is for the drag of the pinion and not the actuall torque on the nut. I was just too green to realize that something's wrong if it only takes about 50 ft lbs or so on the nut to get the 20 some in lbs of drag I was shooting for. The crush sleeve I put in was obviously too short. At least now I will make sure I get a proper crush sleeve and now I know it should take over 200 ft lbs of torque on the nut to get to the point where I have the correct amount of drag. I will also hunt down a in lb dial torque wrench.


Also, please read post 9 and let me know your opinions. Thanks!

 

[bison]

The crush sleeve if re-used may or may not be crushed properly. If there is not enough preload it takes a lot to crush the sleeve more and it may only need to be crushed a more to achieve the preload needed. As stated once it starts to crush the preload will increase rapidly. Most 1/2 in impact guns wont be able to crush the sleeve. A 3/4 with a good air supply will get it. A few degrees of rotation and check it. Keep doing that until you hit the preload you are looking for.

 

[bison]

I understand that the in lb reading is for the drag of the pinion and not the actuall torque on the nut. I was just too green to realize that something's wrong if it only takes about 50 ft lbs or so on the nut to get the 20 some in lbs of drag I was shooting for. The crush sleeve I put in was obviously too short. At least now I will make sure I get a proper crush sleeve and now I know it should take over 200 ft lbs of torque on the nut to get to the point where I have the correct amount of drag. I will also hunt down a in lb dial torque wrench.


Also, please read post 9 and let me know your opinions. Thanks!

You dont torque the nut to get the drag drag. You crush the sleeve to get the proper drag. Your sleeve is probably crushed too far. 200 ft/lbs is not goign to crush the sleeve any further. It probably takes 400-500 ft/lbs of starting torque to even budge that crush sleeve and start crushing it further.

 

[BuickMike]

Thanks everyone. I got a new, correct crush sleeve. This time it took a ton of muscle to get it crushed to the point that I had the correct amount of drag. I actually had to create a brace that bolted onto the yoke and anchored to the floor to hold it steady. With the help of a really good IR, some muscle, and a huge ass breaker bar I got it done. I would have rather gone with the spacer suggestion, however I wanted to get the car back on its wheels over the weekend. Backlash is at .007. Got it all back together and added good ol dino gear oil plus a bottle of GM Limited Slip additive. It's working perfect now.