twohoos

What can I use to hold the diff flange in place while tightening the nut? (Yes, it's a new nut; also plan to use loctite.)

Oh, and should I bother replacing the oil seal?

SgtB

I'd replace the seal. I used a long section of angle iron with holes spaced to bolt it to one side of the flange.

SpitfireS

On both
Replacing (and mounting) the seal is a little harder with the pinion in place (if that's what you're doing) but worth it.

If the diff is in pieces.. replace all seals.

twohoos

Thanks guys, think I have some angle iron lying around somewhere.

I do want to keep the diff in one piece; any tricks or special tools needed for the oil seal?

SpitfireS

IIRC the seal seals on the flange, so you've got some room to pry without having to worrie about damaging a seal surface on the pinion.
Don't create any shavings that might fall in the bearing.

Be very carefull not to overtighten the nut on the allready crushed sleeve.
Use small steps and turn the pinion to seat the bearings every step.

SgtB

Just pry the seal out with a flat head and drive the new one in. I used a very large socket to drive it even. You want to torque the nut until it takes 12in/lbs to turn the pinion freely. The helms has the procedure, and puddydad has a post on here about it.

twohoos

Got it. Thanks again!

SpitfireS

SgtB Posted on Dec 1 2010, 11:34 PM
Don't forget "the helms procedure" is done without the ring in place, just turning the pinion.

If you put bolts in the angle iron in the pitch of the flange holes and use them as pins (or fingers) its easy to hold the flange-tighten nut-turn flange-hold flange-tighten nut, etc.

twohoos

Good point... I think the full Helm procedure actually accounts for the ring gear's resistance, as well as any other minor variations from diff to diff. It says that the final turning torque should be 8-12 in-lb PLUS Tp, where Tp is the initial observed turning torque (measured when the nut is first tightened down to about 14 lb-ft). Or put another way, the process of fully tightening the flange nut should ADD 8 to 12 in-lb of turning torque, regardless of whether the ring gear/LSD/rear housing/etc. are present.

What do you think?

SgtB

Good point. I must have interpreted that post incorrectly. I sort of went by feel anyway. I was just swapping flanges and didn't separate the halves. I'm pulling it back apart soon to see how it's done over the course of a year.