I pretty well understand all the condsiderations for setting pinion depth and carrier shims and setting the patterns to look for seem to determine proper setup better than precision gauges. I already have a dial indicator. I still need an inch-lb beam wrench and some home made pinion spanners.

I've never opened an axle beyond removing and replacing the axles for seal replacement or bent axle replacement. The couple of axles I have worked with had c-clips and the retainer bolt wasn't broken or stuck. Those were serviced while on my back. This axle will be on the bench.

I have a 12-bolt Chevy rear that needs lower numeric gears. Either 3.08 or 3.42 seem to be my best available choices lower than 3.55. If I were satisfied with 3.55, I would have stayed with my BOP for the project and put in aftermarket parts in place of my open 3.08.

The rest of this axle assembly is all new stuff. It has new bearings, new Eaton posi, and a brand new racing gear set. I think it has new bearings in the axle ends too. I don't think the 3.73 will be highway-friendly. I think the swap would cost $200 at a local shop, maybe more around here and I might not like what they do if I watch. It's always best to not watch sausage made if you're a consumer.

What are the cheapest tools I can buy to slip the pinion bearings off and on numerous times while I set up the new gear set? I know I could whittle out an old bearing for trial fit, but I don't have one to sacrafice.

I'm assuming the carrier bearings are new because that is what I was told (axle was gone through for my Nova") and the seller had receipts for much of the work done. So I assume they won't need to be removed to swap the ring gear. Does anyone have advice on this swap with out making a big investment in one time use tools?

I'm an old hand at it so I just use hammers and punches/chisels to remove the bearings. I like fire and ice too when things get tight. I did grind the ID on one when I had access to an ID grinder at work. I rarely use it though. I would put it together with all the same shims that are in it now. Do that and see where you are at. Take the obvious precautions when you install the differential in case the gears are tight. You might just need some small side-to-side adjustments. I know that sounds too easy but that's where I would start. If things are looking way off measure the pinion depth. It's amazing how a crusher spacer will be right with multiply gears sets in the same housing.

I figured on trying the original pinion shim as a starting point, but this axle has never been driven with the current gear set. I have no idea of the competance where they were set up. They guy who bought these parts and put this axle together had the setup done at a shop near Atco, where he planned to race. Then he bought a completed Nova, (smart move IMHO, the Nova looked pretty good) and that changed his plans for this axle assembly. The parts are all new except for the housing, so I don't want to beat on the new parts with a hammer and punch. I would like to use the pinion bearing over again if it is really new as promised. I could grind out a test bearing, but that's extra expense and I will still need to press the final one on.

A new crush sleeve is only $10, so I figure on leaving it out during temporary checking with careful settings of the pinion nut for bearing preload. Once I get a propper pattern, I figure on uinstalling a new crush sleeve just so I never visit the problem again. I know people tap on the side to make it longer for a second try, but I want to do this "by the book".

I think the side to side carrier adjustment might be the easiest part of the job. Am I correct that I can swap the ring gear without removing the carrier bearings? I assume there's no problem with that if I keep things clean. I'm more concerned with the trial and error with the pinion shim. I understand one wants to hit that within two-thou. One of the guys over on Camaros.net who did axles as a business said it was all about obtaining the pattern and he had not measured pinion depth with instruments after setting up a few of them that way. He stated the pattern was the holy grail for setting up a new gear set.

I figure someone who's done many of these would look at the first pattern with a test bearing and the shim thickness would be pretty much on the money, just from experience of reading patterns. On the other hand, I figure on trying all day until I get the required pattern spot-on.

I figure the pinion bearing will be off and on a number of times. So that is the crux of my question.... what is the cheapest way to gently remove and install this bearing for repeated trial fitting? Is there any tool cheaper than a harbor freight press and a bearing splitter?

I'll add to my question with another concern. The engine break-in should be achieved at moderate and high throttle to let the rings seat in properly before the crosshatch pattern is worn down. Some accounts say this takes less than an hour. Then the chance to seat rings has passed. This is at odds with advice for breaking in a new rear gear set, where instructions are to idle twenty minutes with the wheels off the ground, then drive in circles, let it cool and that sort of thing. If you build both as a restoration project, what do you do?

geras are a matched set. i wouldnt advise replacing one without the other!!! if you repllace both, grind the old bearing as you described without installing the crush sleeve till you have it right. then tear down and re assemble for the last time as you should!!!

I understand that. New gears are tested and run by the vendor and they need to match. I need to take out a brand new 3.73 set and put in 3.08 or 3.42. The rest of the parts in the axle are supposed to be new, so I want to save them. I don't have an H stand press, much less a slide hammer. I don't have an old bearing. Should I buy a new one and grind the inside to sacrifice for the project?

I do it the way I described. I've done hundreds of gear boxes that way. Just put it together like you mean it and see what you have. Take it all apart and put it back together the same way. Keep everything very clean. I've worked with hundreds of journeymen machine repairmen, like myself, and we all use punchs or chisels to remove bearings from shafts. Of course we use a hand press when available but it's not necessary. You walk the bearing off the shaft tapping it on either side, alternating. If you haven't done this(walk a bearing off a shaft) before then maybe you should consider some hands on help for that part. You could take the pinion assembly down to a shop and have them 'unstack' and 'restack' on the new pinion.

yes you should buy one to sacrifice. you'll either buy one bearing to grind a 4 to 5 crush sleeves, its your call. i vote the bearing route as its much less of a head ache to deal with!! with the sleeve route, you'll need a press to remove the sleeve and bearing and install new ones each time you go to reset the pinion depth. trust me when i say grind the bearing!! saw this done and had to be done 4 times. luckily he didnt have to press the bearing on and off each time he changed the shims on the pinion!!

Saw it done? How about someone who does it telling you how it's done? The guy you were watching was messing up, obviously? Right?

How about this; Start taking it apart and get a feel for all the parts and report back when you hit a snag. Check the pinion height before you take it out. Take plenty of pictures.

I am good at taking things apart. I'm really good at that part. When I was six, I talked my brother into disassembling his toy top to see what made it whistle. When I was finished, all the metal tabs that held it together had broken off and we had still not found the magic whistle inside. (you probably guessed by now it was the holes punched in the side) If I had been nine, we would have soldered it back together. My mom solved that problem, much to my distress, by transferring tags, title and ownership for my toy top to my brother.

Through life I've gotten very good at taking things apart. That helps understand how things work and that is usually worthwhile if you can put them back together. Later in life I learned how to put some things back together afterwards. I sort of learned to ask about this last step first, before it's too late.

This is really simple. If you follow instructions the maximum amount of times the pinion will need to be stacked and assembled is twice. Worst case scenario would be that you wreck the bearing when you take it off. If the pinion height is off, you measure now much it is off and restack the pinion accordingly. If you measure correctly you only restack once.

I may tackle the disassembly part soon and if I run into a snag pulling the pinion bearing off, I think there is a machine shop or two who have the press. I don't really want to beat on precision parts with drifts and hammers. If it's finessed, I'll have confidence in installing the axle with no worry of latent damage.

The next issue is which gear set to buy. My car came with an 8.2 BOP 3.08 ratio, open. In this Chevy 12-bolt, there seem to be two ratios available in the aftermarket that fit my Eaton posi 12-bolt carrier. I can find 3.08 and 3.42. It seems like Motive, Yukon, Richmond and unbranded are the choices.

Which brand is best? Would I see that much seat of the pants difference with a 3.42 compared with the 3.08? I don't care about 1/10 second on the track. This will be behind an upgraded TH400 and stock low compression 400 motor.

Which brand is best? Would I see that much seat of the pants difference with a 3.42 compared with the 3.08?

Richmond and YES Very big difference.

You'd feel 11% more acceleration if your pants' seat was delicate enough!

That is just what you get from a simple math equation. 11% is nothing to sneeze at BUT you will feel more than that when you can get your Pontiac engine up in RPM's quicker. It's the same logic behind using a stall convertor. The sooner your get up into the 'power range' the more power you will feel. Going from 3;08 to 3;42 can make a big difference off the line. When you get your 'sled' moving faster sooner it's easier to stay in that power range. In my experience, a bog with a higher gear off the line will hurt you through the whole quarter mile. It is possible to tune a car just right to eliminate the bog with a 3;08. Having said that, it's much easier to get acceleration out of a set-up with 3;42's. IMO there's a world of difference....