8.75 rebuild tips

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7dart0

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Evidently nobody in my area sets up ring and pinions anymore, so I'll have to try and do it myself.

Can anyone offer any tips on setup like torque specs. It's for a 742 case. New Richmond 4:10 gears new suregrip from doctor diff.

Thanks
 
Take a set of old pinion bearings and hone out the inside so they slide on and off the pinion that way you can set up the 17 or so inch pounds that you need to set the preload at. You set the preload without the seal installed.

If you have the old pinion that was in it before, pull that inner bearing out and take those shims and put on your new pinion. And then take that old bearing hone it out, put it on, do the same with the front pinion bearing and get your preload set.
I like to set my sure grip unit in the refrigerator for a few hours and let it cool down while I put the ring gear outside in the sunlight so that it can warm up and then assemble them after they both reached the temperatures that I want. That way the ring gear just slides right on.
I would put the carrier bearings on before I put the ring gear on the carrier.
Then set it up in the pumpkin, set your backlash, check your pattern, if its pattern is good take it back apart and put the new bearings in place of the honed out ones. Install the seal, put the carrier back in but before you put the carrier in check your preload again on your pinion, with the seal in it it'll be five or six inch pounds more than what it was before.
Then set your ring gear back up. Check you gear pattern agin.
Watch when you tighten the side adjusters don't bury the ring gear into the pinion. Adjust one side then the other a little at a time till you get your backlash where you want it. Snug down the caps check your backlash again check your pattern.
If the pattern on the teeth is wrong you want to have found that out while you still had the setup bearings on the pinion so that you can adjust that pinion in or out of the case as needed.
Lube the bearing do not set it up with dry bearing. Check the backlash in 3 or 4 places.
 
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Great info. Thank you. I know I'm probably just over thinking things. It seems pretty straightforward. I figured if I can put a crank and bearings in my motor I could do this.
 
Should I prelube the bearings with gear oil or something else?
 
That's the best tip is about the inner (large) pinion bearing. But you only have to hone the one, the outer (small) is a slip fit, not a press fit. Once the inner bearing is honed for a slip fit, it makes it very easy to set up the proper shim to get pinion gear depth correct. Whenever I do one, I use a new bearing and hone it, since using an old bearing will effect your final outcome. Bearings are cheap compared to having to buy another ring and pinion because you got it wrong. Do it once. Do it right. It's always cheaper in the long run.
 
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Great info guys. I appreciate it very much.

Anyone have a part number for the extra pinion bearing for a "742" case
 
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