Axle setup questions

[Collin the Hen]

I'm really leaning on changing the gears in my CJ7 myself. If the bearings are fine in both the carriers, are new bearings still necessary? Would I need to get rebuild kits for both axles? I'd be going from 2.73 to 3.54 so the carriers are different.

A mechanic I know said he wouldn't be able to get the axles done until Christmas because he's backed up, but he'd let me borrow the equiptment to do it myself. He mentioned one shop he would trust with axles, but they may not want to install used gears. If they break for being junk, then they get blamed for a bad install. I'll call them tomorrow to get the beef.

This would be a pretty stout venture, so advise is much appreciated!

 

[Bounty__Hunter]

You can reuse bearings if they aren't giving you any problems. You'll need a way to remove them without damaging them if you have to change carriers.

The front d30 should use the same carrier, not sure about your rear axle. WHat model axles do you have?

 

[jps4jeep]

if you have a 44 rear, you will be able to re-use the carrier, the break over was at 4.10:1 gears. for the M20.. Not sure, but you should be fine.

As with bearings, I also agree, but my practice is that if the bearings are older than 2 years, it is cheap insurance to change them while in there. you can make/buy a press, or a shop can press them. My local shop charges $5 a bearing.

 

[jps4jeep]

To add, I was very hesitant to gears for the first time, I was lucky enough to also have a friend who let me borrow the tools, and he was also kind enough to walk me through the procedure on the front axle with plenty of tips and tricks in his off time in exchage for a 30 pack. I have since done about 10 other gear sets. once you understand the fundamentals, it's not all that difficult, just time consuming.

 

[Collin the Hen]

I have the Dana 30 and amc 20. I know for sure that the rear has a different carrier. If the front is the same then that would be one less step. The mechanic said you can take out the carrier and put it back in with all the shims that were in it, and 9 times out of 10 the position will be fine. I also didn't mention that I would be buying narrow track axles with the gears in them.

Also, if you guys have any tips or tricks for this job, I'd love to hear them.
Thanks!

 

[currupt4130]

I have the Dana 30 and amc 20. I know for sure that the rear has a different carrier. If the front is the same then that would be one less step. The mechanic said you can take out the carrier and put it back in with all the shims that were in it, and 9 times out of 10 the position will be fine. I also didn't mention that I would be buying narrow track axles with the gears in them.

Also, if you guys have any tips or tricks for this job, I'd love to hear them.
Thanks!

That mechanic is a fool. The same shims are a good starting point, but very rarely will it be as good as you can get it. When you're dealing with new gears and new carriers, you need to go through an entire setup. Hell, I go through it with just new gears.

 

[Collin the Hen]

That mechanic is a fool. The same shims are a good starting point, but very rarely will it be as good as you can get it. When you're dealing with new gears and new carriers, you need to go through an entire setup. Hell, I go through it with just new gears.

This would be with the same carrier, just different gears if indeed the 3.54 ring will fit on my 2.73 carrier. Sorry, I didn't clarify.

He's done this many times before, and he is NOT a fool. He said that he did this with a grenaded Dana 60 a guy had in his hauler, and so far, after its over-weighted payload, it's fine (it grenaded from being over-loaded).

Thanks for your input, though. Any other advise is great.

 

[jps4jeep]

Agreed that mechanic is an idiot.. I tore up a set of gears while back, I simply swapped the ring and pinion, same ratio, for a new set.. Same carrier, didn't replace any bearings but the pinion bearing (DOA.. Caused the carnage) and my gear pattern was no where near acceptable.

While I will not argue that he did it, and it has not blown up yet, a improperly et gear will prematurely fail. a properly set gear in a vehicle that is generally not hammered on, should last near 200K miles.

 

[Collin the Hen]

I bought those axles today, so it's going to happen. I'm going to play it safe and buy rebuild kits. I have to have new pinion nuts and some sort of setup bearings anyways, so I'm just going to buy kits.

Any good recommendations? So far, I'm shooting for Superior, but I'm not sure how they measure their shims. I've read that it's less complicated when they're measured in "solid" thousandths instead of like 3.5 thou. I don't want price to be an issue, I just want the best.

Also, do any of you guys know of any tools that can be made for this job? I've already made a 1/4 bar to hold onto the yoke to get the pinion bolt out. That was nice. I also read in a Pirate 4x4 article about using bearing cones to press in bearings.