Welds in diff cracked

[JeepN4kc]

Well I dropped the rear diff cover this morning to swap-in fresh gear oil and get a look at the welded rear-end in my new to me XJ.
I found the welds are cracked.
In this pic you'll notice lower-left/upper-right:

Rotate the axle and you'll notice upper-left/lower-right:

I'm an XJ newbie still learning, especially when it comes to welded differentials, so I'm not sure of my options. I've only driven this thing 20-30 miles since picking it up about a month ago. If put new oil in, pop the cover back on, and continue to drive with this going on in the rear I assume it will chew the welds up and really do some damage eventually? Can this be rewelded? Can the spider gears be replaced? Should I just get a new rear-end?

 

[Porch951]

When welding the spider gears it's important to make sure they're pre-heated as much as possible (if you have an acetylene torch that helps).

But eventually they all crack. It's not a big deal...just drive it, it's not going anywhere. When the crack gets big enough that you can feel the slop, weld it again.

Or just buy a mini-spool, they're cheap.

 

[JeepN4kc]

Yeah - I'd read the "pre-heat" when I was researching welding diffs. It was built like this whan I bought it (I don't know the first thing about welding, lol, need to learn).

Anyway, thanks for advice.

 

[souske]

What axle is it?

 

[85xjwoody]

I had that happen to me in my 8.8. I just heated up the welds and spiders with a propane torch for a bit and welded it back up. Still holding up to this day in another jeep for the past four years. Make sure you use a stick welder or a GOOD wire feed welder.

 

[JeepN4kc]

What axle is it?

Chrysler 8.25 29 spline

 

[souske]

I would look into an Aussie

 

[JeepN4kc]

I would look into an Aussie

I was thinkin this, or Detroit, or Trac-Loc. IDK - but I think my options are steering me towards replacing the carrier and spiders with a true locker. I could swap a salvaged axle but I would eventually want a locker in that. My current R&P don't have any damage (I think my find this morning was a blessing in disguise as I came across a ticking time bomb before it went off).

 

[Nealio240z]

I let the cracked welds in my d44 go for some time- ended up in both tires locking up at 35. welds broke and jammed the r/p gears and stopped me dead in my tracks. Had to remove the rear drive shaft, diff cover, carrier and gears and re installed cover. Drove it 40 miles in front wheel drive 4 high =)

Fix it before its a problem.

 

[JeepN4kc]

I let the cracked welds in my d44 go for some time- ended up in both tires locking up at 35. welds broke and jammed the r/p gears and stopped me dead in my tracks. Had to remove the rear drive shaft, diff cover, carrier and gears and re installed cover. Drove it 40 miles in front wheel drive 4 high =)

Fix it before its a problem.

This is exactly what I mean when I say I think I found a ticking time bomb before it went off. Glad nobody got hurt when yours grenaded.

 

[Porch951]

And how are you going to get everything out of that carrier to put an aussie in?

 

[Vanimal]

i was just wondering that.

 

[MoparManiac]

Depends on if the gears were welded to the case or not.

If not, pull the ring gear and then crosspin. Rotate the spiders until they are facing out of the carrier.

If you can't just pull them out, start hacking.

 

[JeepN4kc]

And how are you going to get everything out of that carrier to put an aussie in?

Yeah - good point. I'd say after a day's worth of asking and reading yesterday the carrier is done. My locker, or LSD, options will have to include replacing the entire carrier. Talking with a local 4x4 shop since the R&P are intact and I'd doubtfully change gears all they'd have to do in addition is check the pinion depth and setup backlash.

I'm behind the eight ball as far as the learning curve with all this stuff because it is happening before I'd planned on addressing it. All I wanted to do was change my diff oil yesterday and inspect the welds from the PO. Once I got in there and took a look - :explosion - all my plans were blown to $h!t !!!!

What I really wanted to do was combine some uni-stiffeners with the TnT belly pan I picked up from a local guy for $200 (it's brand new, never used). Then replace the rear shaft with a front ds I picked up for $30 and put a SYE on the 231. That stuff I had started researching about 2 weeks ago.

This rear diff/locker/carrier/cracked welds blah, blah, blah - I'm learning as I go.
Plus, my other plans didn't run such a hefty tab.

 

[Porch951]

You can probably do the diff stuff yourself as long as you're careful.

If you want to go cheap, grab a carrier off ebay and get an Aussie.

 

[MoparManiac]

You can probably do the diff stuff yourself as long as you're careful.

If you want to go cheap, grab a carrier off ebay and get an Aussie.

Not something I would recommend if you don't have a dial indicator.

You want the backlash to be right back where it was when swapping carriers.

And carriers aren't exactly the same down to .001". Including new bearings.

 

[Vanimal]

Not something I would recommend if you don't have a dial indicator.

You want the backlash to be right back where it was when swapping carriers.

And carriers aren't exactly the same down to .001". Including new bearings.

the dial indicators at harbor freight aren't actually that bad, i keep one around for car type stuff. i checked it next to my starrett and it was pretty spot on. they were like $20 with a mag base IIRC. makes it hurt less if you kock the mag base off the housing by accident. the biggest PITA will probably be pulling the bearings off the carrier, and without ruining them so maybe you can make setup bearings, otherwise it'd be a bit of a bitch to set the shims up.

used it when i shortened my driveshaft too.