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- - pinion nut (https://67-72chevytrucks.com/vboard/showthread.php?t=514809)

hey im looking for the tourqe spec. on the pinion nut on the rear end..i cant remember yes im getting old.:metal:

What kind of rear end? If its a 12 bolt there really is no spec, just tight enough to preload the pinion bearings correctly.

You need a rotating torque spec.

^ x2

The in-lbs of rotational effort required is different for new bearings and used bearings too.

You really need a dial indicator type inch-pound torque wrench to do it properly.

12 bolt 1/2 ton posi..new bearings..i know the crush sleeve has to crush but..i dont want to over tighten...

The proper way to do it is to have a beam type torque wrench that goes in small increments, 1/4 or 3/8" drive, so that you can read 5 inch pounds of rotating torque. To get an accurate reading make sure that the pinion races are seated ALL the way and the bearings are lubes with oil.
First you tighten the pinion nut so that the slack in the pinion is just taken up. Then tighten the nut a little at a time, measuring the rotating torque after each tightening, until you get the 5 inch pounds of rotating torque. You are then done. The crush sleeve is now "crushed" and has the proper load on the pinion bearings.
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I used to use a 1/4" beam type torque wrench to do this but after doing a few I just do it my hand now. This is how I typically treat pinion bearing pre-load now:
On crush sleeve type rear ends I usually try to get a new pinion nut but re-use the old crush sleeve, I know youre not supposed to do this but Ive done plenty and never had one come back. After Im sure the pinion depth shim is correct I put red loc-tite on the nut and tighten w/ my 1/2" impact until all the slack is gone. After that I alternate between a few hits w/ the impact and turning the pinion by hand. Keeping in mind that bearing failure due to too little pre-load is far more common than too much pre-load I set pre-load on new bearings to the point where its hard to turn the yoke w/ your fingers but you can turn it w/ your whole hand w/o too much effort. The bigger the rear end the harder it should be too turn(dana 80 should be harder than a 10 bolt etc.)
If I used a beam type wrench Id probably set a 12 bolt at somewhere between 5-10 in/lbs rotational torque w/ old bearings and 10-15 w/ new bearings

15 in lb used bearings 25 in lb new bearings that is rotational force
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