sreeb

I'm progressing through a c8.25 regear. I have a few questions now and likely more later.

1) I'm about to press the bearing off my old pinion to make a setup bearing. Do I replace the bearing races in housing before or after I set the shims with the setup bearing? Or does it not matter?

If I had to guess, I would pair the setup bearing with its original race but procedures I have seen on the web suggest changing the races first.

Ultimately, it won't matter since I will check again with the real bearings but I don't want to make things harder for myself.

KCXJKID

Also wondering this..Anybody?

Marks2000XJ

I just got mine. I saw some install directions in there but have not looked at them yet. I will dig them out and read them and report back.

sreeb

I'm not sure you will find anything about setup bearings.

The FSM shows using a special tool that measures the distance between the bearing seats and the end of the pinion.

My gear set instructions don't discuss setup bearings either.

Right now, I'm still trying to remove my "setup bearing" from the old pinion. Just picked up a "large bearing separator" from HF and will have another go with that and a press tonight.

94XjSport94

I changed the races first. I used a Yukon bearing puller to remove mine, then took a dremel to the bearing and opened it up to slide over the pinion.

Obviously there are no carrier shims, so I just pressed those on and worked on setting pinion depth within the correct BL.

Here is what I ended up with:

There are a few good write ups between JF and NAXJA.

Marks2000XJ

I did not see anything in there about that. Install instructions are pretty generic. I assume you would just remove everything, clean it all up and start installing new parts.

I know there is a chart showing old bearing and new bearing pinion pre-load torque specs. Which leads me to the question, if you use your old pinion bearings and new races to set up the pinion depth and using the pre-load specs (old and new bearings) accordingly, will your pinion depth be off when you install the new bearings?

Marks2000XJ

Did you make you a home brew tool to adjust the carrier back lash? I saw where people have welded a 36mm? nut onto a long piece of pipe and then welded a half inch socket fitting on the other end for the torque wrench. Instead of buying the "special tool".

Nice pattern on the gears btw. Hope mine turn out that good.

sreeb

That's what I made.

The hex cutouts in the adjusters are 1.44" across.

IIRC, I used a 1-1/8" nut which turned out to be a little too big so I had to mill down all the edges a little.

The spark plug socket works out really well as it is much more convenient to us a box wrench than a ratchet when making adjustments. If you don't have one, I would well another nut on the end in preference to an old socket.

sreeb

This was much more trouble than I had hoped. The bearing race really didn't want to come off the pinion. The HF bearing separator (which is kind of crude) popped off mangling the bearing cage. I re-contoured the bearing separator with a die grinder so it could get more securely under the bearing race and eventually got it off. Finally spent quite awhile bending the cage and reassembling the bearing.

I'm firmly in the setup with original races camp now. I don't want my beat up old rollers and mangled cage getting anywhere near my new bearing races.

Marks2000XJ

Cool. I guess the other pic is a breaker bar for to hold the pinion while cranking down the pinion nut.

sreeb

Yeah, its a piece of garage door opener T track from the bone pile.

Marks2000XJ

Keep us updated on how you did your install. I will be doing mine here soon. Still gathering a few tools and gauges.

Doing the heater core and a/c first. Probably this weekend since I have a few days off.

sreeb

Tonight didn't go very well. I had a couple of issues related to installing a Detroit Locker in conjunction with re-gearing.

First an issue with the axle spacer which caused me to have to remove and re-install the ring gear. If you put it in like the first photo and then install the ring gear, you won't be able to remove it. I figured this out early but it would really suck if you didn't figure it out until it was time to install the axles. Best bet is to remove it and leave it out until you ready to install the axles.

sreeb

My bigger problem is that I have interference issues between the end of the pinion gear and the case of the Detroit Locker. Once I tighten down the bearing caps, the pinion wedges against case of the locker.

The locker case is much larger the OEM carrier so pinion length is a little more critical than it would be otherwise.

It is possible that there is a problem with setup bearing as I had trouble removing it from the old pinion but the pinion feels OK when I spin it.

I will be calling Eaton technical support in the morning.

RWKHausSupply

That interference is only typ with 3.73 and numerically lower ratios.

Make sure you use a good amount of lock tight on the RG bolts, as the C8.25 uses such a small RG bolt that the torque is minimal and common for the bolts to back out of poorly assembled diff's.

As for that HF puller. Its a separator and have yet to see anyone use it with and successfulness, when pulling a pinion bearing. You need a Diff bearing puller. Another one of the Diff guys tool arsenal that makes paying the 125$ with it to the average Joe.