[drewm]

I am in the process of setting up my 71 olds rear for my 66. I know that to correctly set the pinion depth, I will most likely be removing the pinion gear a few times in order to get the right shims. So I have honed an inner bearing so I can remove it without having to press it off each time. However, my outer bearing (both old and new) are obviously a press fit also, so I was wondering if I should hone the old outer bearing so it can be removed easily? I would assume that the new outer bearing should be used only one time, once the depth is set? The only you-tube video I have found shows the person using the new outer bearing for setup, which means he had to take it off and on a few times. That just seems like a bad idea to me.

Thanks,

Drew

[Cliff R]

I "cheat" here and polish the new pinion gear at the large bearing surface in the lathe so it still has a slight "interference" fit but doesn't require a clam-shell and 20 ton press to get it back off. If I need to make a change I can place the clamshell across the big shop vise and smack it with a BFH and brass punch and it will drop out of the bearing, or a quick trip to the press and it pops out with minimal force.

Decades ago you could simply re-use or duplicate the original pinion shim and good to go 98 times out of 100. Sadly those days are long gone and you will need to duplicate the pinion depth etched on the back of it, or start "middle of the road" with pinion shims, do a quick set-up, learn to read patterns and move it accordingly.

I've done scores of them here in the shop with perfect success. Two things that I do recommend are the "adjustable" side shim packs instead of solid shims or combinations of multiple thickness shims, and a suitable set-up to effectively "crush" the collar for pre-load.
Even better would be a solid spacer with adj shims.

Most folks do them in the vehicle which works fine if you have a lift, someone difficult laying on your back......IMHO I have a HUGE vise that will hold the entire diff if it's out of the vehicle which is much preferred vs doing them still in the car.....but you can be effective either way...........Cliff

[Formulajones]

The outer bearing next to the pinion shouldn't have a hard press fit like the inner bearing does anyway. Those outer pinion bearings are actually pretty easy to install and remove with light taps using a drift. I like to use a soft mallet and just tap from the yoke side and use my other hand to hold and catch the pinion when it comes free of the outer bearing. It's actually very easy to do and shouldn't require a bunch of force.

It's that larger inner bearing that I generally modify for a nice slip fit to make removal easy to change the pinion shims.

[drewm]

Originally Posted by Formulajones

The outer bearing next to the pinion shouldn't have a hard press fit like the inner bearing does anyway. Those outer pinion bearings are actually pretty easy to install and remove with light taps using a drift. I like to use a soft mallet and just tap from the yoke side and use my other hand to hold and catch the pinion when it comes free of the outer bearing. It's actually very easy to do and shouldn't require a bunch of force.

It's that larger inner bearing that I generally modify for a nice slip fit to make removal easy to change the pinion shims.

Thanks, Ill give it a try with the new bearing. I was just concerned that a few off/on cycles with the new bearing would damage it somehow.

[67Fbird]

yes the OUTER pinion bearing will go on/off with very little persuasion. I too have an INNER bearing I honed just for set up stuff and have found it to be within .001" of the NEW bearing. of same BRAND and number. Obviously your still going to run a pattern at final. The worst I;ve had change....was still within GOOD pattern--> Great pattern. i will say that using a set-up bearing always go for the "perfect" pattern...this gives you a little wiggle room when you swap to the finish bearing.

[Cliff R]

"I was just concerned that a few off/on cycles with the new bearing would damage it somehow."

I doubt if you could hurt them unless the clam-shell slipped off for some reason and destroyed the cage. You might gall the pinion bearing surface especially if they got started a little cock-eyed for some reason.

I prefer not to use honed set-up bearings do to slight deviations in manufacturing being a possibility. It's certainly a LOT easier to gently polish the bearing surface than hone the inners of a bearing, that is some really hard material! I still remember decades ago making custom set-up bearings for an early Dana 60 when they had the shims under the carrier bearings (not a good set-up IMHO). I honed on those bearings for what seemed like hours to get them to slide on and off with minimal effort.........

[HoovDaddy]

I have test bearings in my box from the old days. Not worth the extra time if a bearing gets damaged when your on flat rate.