01 4x4 4 door
pulled the axles to change the bearings and I noticed what seems quite a bit of side to side movement in the carrier. now this is without the axles. but I'm getting about 2 mm of side to side movement . It looks a lot worse, but that's what I measured... about 0.078 inch.
Is this excessive for the 7 5/8 rear end? and will the amount change once the axles are back in place? one axle is showing pitting so I'm hoping I'll have time to hit a junkyard tomorrow... almost $200 for a Dorman

 

By side to side play to you mean on the carrier bearings? if so that is bad... there should be preload on them, no slop allowed.

Or are you talking about backlash in the ring/pinion?

 

Your gear carrier should have no side to side movement as KM346 said. .078 gear backlash is a lot. Either way, sounds like you need to replace a few parts.

 

thats what I was afraid of. I can physically move the ring gear/carrier assy. from side to side, which also means some rotation as well . I'd say this play is the source of the "chunk" when going from drive to reverse.
Crap, and I was hoping to have it on the road this evening. looks like I get to dig a little deeper into this rearend.

Does this sound like the way to start?
keep the shims separate when removing the carrier, and inspect. replace the carrier bearings (differential bearings)
I don't think I'm up to replacing the pinion bearings... I didn't notice any side to side play when I pulled the driveshaft, and no leakage that I could see.
reassymble check for movement, and add shims if needed till there is no side to side play.
then ... the tricky part checking the tooth contact patch. moving shims from one side to the other until contact patch is ... centered? not on the edge of the tooth?
Thanks , I REALLY appreciate the advice.

 

Well, I found one of the carrier bearings was pitted pretty bad. unfortunatly no autoparts stores locally had shim packs for the 7.625 rear end. I'll try to hit a local trans parts warehouse that claims they carry diff parts.
Should I worry about the tooth contact patch (I'm trying hard not to mess with the pinion) or shim it till there is next to no play between the teeth? and no side to side play in the carrier assy? ( with the new bearings on the carrier the old one piece shims won't fit, just a couple of thou to thick.
I'm learning way more than I wanted to on this...

 

When my rear differential failed, I went and found a complete rear axle. Guy wanted $100, which is cheaper than the ring and pinion, let alone the setup.

 

Pick n pull had one 4x4 '98-up s-10 that would fit the bill ... axle had already been picked. lots of older with drum brakes.
best other price was $350 for a whole axle.
I thought I could get off cheaper fixing the problem. I don't know what side of that price I'm going to come out.

 

If you figure:
$175 for gears
$75 for bearings and seals
$250+ for someone to install said gears
$200 for an axleshaft

Looking at around $450 just in parts, but at least you know it's all new.

 

I probably came out slightly ahead at close to the $300 mark.
but then I didn't replace the ring and pinion. there were no chips and I couldn't see any wear .
I came away with a diff that I know whats inside. a JY one is a ticking time bomb ... does it have a month, a year or ten years.
I also have taken some of the mystery out of another part. so now transmissions is problably the only part I'll be hesatant to "rebuild"
Thanks,