I like the way you think, and there were some tools I had to have . It was a negotiated fathers day gift .

 

What do you mean exactly?

 

The pinion gear likes to run a little snug to insure proper clearances at the contact point of the teeth and also the nut will stay tight due to the resistance of the crush sleeve. I have fixed hundreds of diffs and the amount of drag isn't as critical as most people think. As a diff wears out the pinion bearings get loose and the nut can back off. When you tighten the nut back up it crushes the sleeve a bit more and restores the drag to the pinion bearings and also restores the needed resistance to the nut to keep it tight. Keep your inch pound wrench in the rollaway and just make sure it has a little drag. The worst wifes tale I've heard in here is that you can mark the position of the nut and return it to that mark. That only assures that you are back to the same place you were before but with more chance of the nut coming loose. You can also use a new nut and stake it with a punch but not necessary if you do what I said. I have seen diffs with lots of miles with pinions set way too tight and many with no drag at all and they were still working fine.

 

I imagine some of this will be finesse, but is there a torque amount I should be looking for, or should I tighten it a half turn past where it was before?

Sorry, not meaning to hijack the thread, but maybe my confusion could help others in a similar spot.

 

I realize this is an old thread, but I just have to add that what I quote above is precisely what 2 Ford truck mechanics I spoke to told me they do when replace the pinion oil seal. They count threads, reuse the same pinion nut with a new crush sleeve and oil seal and set the nut so that the same # of threads are exposed.

I guess that isn't correct after all.

 

In a perfect world, yes, there is a torque setting but it needs to be measured with the axles pulled out so the diff can spin freely. You measure the rotational force required to maintain the pinion gear and ring gear spinning (with the axles pulled out) with a beam-style torque wrench. If my memory serves me it is 15-30 inch pounds for new bearings and half that for used bearings.

Most mechanics will not do it this way because it is time consuming.

 

There are specs for everything but most are for reference. If you tighten the nut to where there is a little drag it will be fine providing the nut is tight.

 

Well...the problem is, for those of us with little real-world experience, "a little drag" is a unit-less measurement which we cannot duplicate. But I do appreciate that most experiences folks would know what you mean.

When you say this, do you mean with the axles in or axles out?

 

Lex the ''drag'' should be checked without the axles (or anything else) but us seasoned diff guys know the ''feel'' we're after......
...... of course the drag is measured after you start spinning the pinion gear in the housing ....

 

Right, I have seen them so tight I could barely turn them and still working perfectly after many thousands of miles, and I have seen many with almost no drag because the drag disappears as the bearings wear. The only purpose of the drag is to assure you that the bearings are snug. Everybody that doesn't have experience with them gets too hung up on inch pounds. I have rebuilt hundreds of rear ends and never touched an inch pound wrench.

 

Where were you when I needed you during my rear diff rebuild?

 

N. Ca........lol

 

On the bright side, after 30 months, no leaks or noises.

 

 

By "drag" are you referring to the ease the pinion shaft is turned before the nut is tight when compared to how easy the pinion shaft turns after you have tightened the nut?

Jeff