tightening the pinion gear

[muff]

I replaced the ring and Pinion gear in my 12 bolt GM rear.

I first need to tighten the bearings and the crush sleeve. Is there a proper way to do this. I have read that it get 8-15 Ft pounds of rotational torque. Is this true and if so what is rotational torque? My best guess is with the rear in the air you spin the rear tires with the torque wrench on the pinion nut and the wheels should spin with 8-15 ft pounds on the torque wrench. Is there a spec for the torque of the nut that hold the driveshaft to the pinion shaft?

I am looking for any answers before work

Thanks in advance
Muff

 

[roadtriper]

Muff, the crush sleve /Bearing preload is done without the carrier and ring gear installed in the housing. first off was there a shim between the old pinion gear and the inner bearing on your original setup? if so was the shim installed on the new pinion gear? this establishes pinion depth setting to original specs. to crush the sleve you need to hold the companion flange with something with lots of leverage. the proper tool has a flange with a hole in the middle that bolts to the ujoint bolt pattern on the companion flange and alows a socket through the middle to tighten the pinion nut. this holding tool has a handle thats probably 2 feet long. and you will need a Breaker Bar or cheater pipe about the same length on the pinion nut. the crush sleeve can be somewhat stuborn to get crushed. it usually takes two people. I Have used a Big Ass Pipe Wrench to hold the companion flange. the torque spec they give is just the rotational drag on the assembled pinion/bearing,seal assembly. personally I always feel that it's a bit tight using the book specs.??? I've always done it more by feel and experience which is hard to disseminate in an email basicaly you want to crush the sleeve and tighten things till all the play is gone from the bearings and then you want a little bearing preloead. but not much. once you get to the "no play" stage you need to go real slow and easy. if the crush sleeve is crushed too much you need to replace it with a new one and start over.
Perrsonaly when I set up a pinion, I crush the sleeve with out the seal installed and I use the old pinion nut. this way I get a feel for the bearing preload without the drag of the seal. once I'm happy with the bearing feel I remove the companion flange, install the new seal. and reassemble with the new pinion nut and torgue it to spec. the torque spec is not enough to crush the sleeve any further. now youve done the easy part! next you need to set the ring gear backlash and carrier bearing preload which is done with selective shims on the 12 bolt. getting the correct shim combination can sometimes become a scavenger hunt at dealerships and local tranny shops etc. hopefully your rear end kit came with a shim pack? RT
BTW be sure and prelube the bearings a bit before assembly

 

[crazy4offroad]

I put a rag on the pinion teeth to help hold it with my left hand and not get hurt by the teeth, then tighten the nut with a 1/2" impact capable of at least 450 ft/lbs of torque with my right hand. It is slow going but once you get to where you can feel resistance in turning the pinion switch to an inch-pound torque wrench to check rotational torque. I usually just check it by feel. It should turn freely with a little drag but when you spin it and let go it should stop and not keep spinning. Your spec of 8-15 ft/lbs is way too much, it should be inch-pounds.

 

[muff]

Thanks for all the info. So............. what you guys are saying is i need to remove the rear axles, carrier and ring and pinion agian in order to crush this sleeve. It can not be done in the rear. Wow I am glad that I asked before doing. YOu guys saved me alot of money time and headaches down the road.

 

[crazy4offroad]

NO. You leave the pinion in the axle housing but the axleshafts and carrier with the ring gear MUST come out.

 

[MrMarty51]

The pinion seal also must be removed,A long pipe wrench,long enough to reach the floor or a block of wood helps to hold the pinion yoke while tightening the pinion nut to get the sleeve to crush.go slow,take Your time as once the sleeve begins to crush it goes fast.
I have,if I crush just a tad too much,find a .010 or so shim and stack on top of the crush sleeve,but,if You take Your time You should`nt have this problem.

 

[muff]

Thanks for all the information Roadtripper and Crazy4offroad. Rear is back together. Just put 40 miles on it and seems good thanks again

 

[crazy4offroad]

Hey by chance did you used high-strength red thread locker on the pinion nut? If not, take it off and do it now before you forget, it WILL back off.

 

[roadtriper]

Thanks for all the information Roadtripper and Crazy4offroad. Rear is back together. Just put 40 miles on it and seems good thanks again

Glad it all worked out and you're back on the road! is she quiet?