Rear End whir after traffic incident

[Some Random Guy]

Team, I'm looking for a bit of help isolating an issue before I try the dealership. I had an incident earlier today that took me from 100% brake, to WOT, to 100% brake, back to WOT. All 1st gear, I have a manual transmission. Afterwards, my rear end was making a lot of noise. Specifically when coasting (in gear, or in neutral) and it varies with speed. It's pretty loud. At first I thought one of my fender liners had somehow started rubbing, but that's not the case.
My best guess is I messed up the diff, either a bearing or knocked the backlash out of spec. Anybody else got ideas to check on my own? I don't want to pull driveshafts, I was supposed to go cutting trees in the mountains tomorrow. Looks like that's off now, but if I need to get it to the dealer I will have to do that within a few hours. I'm more inclined to get it to a diff shop, but the only reputable one that doesn't charge 4-digit prices for diff flushes is quite a ways away and usually booked out.
I'm going to go look at prices on 60's, I'm not dumping too much into the stock D44 if I did butcher something. Horrid driving has become pretty common, so I suspect a similar incident will happen again within a year.

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[MKC JL]

Bad pinion bearing will cause that also.

 

[AcesandEights]

Driving shouldn't cause that.

 

[Some Random Guy]

Bad pinion bearing will cause that also.

I talked to Yukon, they're highly doubtful of that (fingers crossed they're right). I got the rear end up on jack stands and the passenger side rear is making noise when I shake it. There might be some play. I'm guessing wheel bearing, but have a local shop taking a look Tuesday. I have a dealer appointment 1 week later (had to lock it in now), so hopefully I'll know by then if I need to pull the tazer.
I've never heard of a wheel bearing being damaged during a braking event, but then again I don't know all the ways oversized tires can mess up a drivetrain. I really can't wait for my car to be delivered so I don't have to daily drive this and risk stuff like this.
If it is a pinion bearing, I might be better off applying the labor cost to a Currie-60 and installing it myself.

 

[Pinion]

If you got rear ended, someone else should be coughing up the dough.

Unhook the driveshaft and get the rear tires off the ground. Spin the tires, and then spin the input flange.
Check for noise. Repeat at the transfer case end.

 

[Some Random Guy]

If you got rear ended, someone else should be coughing up the dough.

Unhook the driveshaft and get the rear tires off the ground. Spin the tires, and then spin the input flange.
Check for noise. Repeat at the transfer case end.

Not rear-ended, fortunately (?). Just some heavy load on the drivetrain. I was dumb enough to speed after them, but not sure which event caused the issue.

 

[AlgUSF]

You seem sold on getting a 60.

 

[Some Random Guy]

You seem sold on getting a 60.

Lol, I told myself "2 driveshafts or a damaged ring/pinion and I'll replace the offending axle" when I went for 39's on non-reinforced D44's. If my current issue is a pinion bearing, I'm worried labor will come in around $1k. Labor out here is expensive. Makes me want to cut my loses, because if this happens again I'll kick myself for not just putting in the 60's before dropping $4k in labor into the 44's ($2k regear, 2x $1k repairs).
Also, we overshot some savings goals recently so I will have some extra budget in about 2-6 months.

 

[AlgUSF]

Lol, I told myself "2 driveshafts or a damaged ring/pinion and I'll replace the offending axle" when I went for 39's on non-reinforced D44's. If my current issue is a pinion bearing, I'm worried labor will come in around $1k. Labor out here is expensive. Makes me want to cut my loses, because if this happens again I'll kick myself for not just putting in the 60's before dropping $4k in labor into the 44's ($2k regear, 2x $1k repairs).
Also, we overshot some savings goals recently so I will have some extra budget in about 2-6 months.

No judgement here! I have a sport with a 30 in the front and want to regear due to the 6MT and desire for larger tires. I'm like, "Why put all of that money into a Dana 30 when I can get a 44 already geared up and just regear the 44 in the back?".

You're looking for a bit better hardware than I am, but we are in the same boat.

 

[Some Random Guy]

No judgement here! I have a sport with a 30 in the front and want to regear due to the 6MT and desire for larger tires. I'm like, "Why put all of that money into a Dana 30 when I can get a 44 already geared up and just regear the 44 in the back?".

You're looking for a bit better hardware than I am, but we are in the same boat.

Wish you were closer! I was thinking of teaching myself to re-gear on the removed D44 if it doesn't sell quick. My next car purchase will probably be a V8 that I build to race, so I gotta complete my shade tree degree. I think you're close to ChevyMitchell though. The D30 might be a great learning experience for a regear alongside the rear D44.
Budget drives these things though, for all of us. Even if you're "rich" you have plans for that money to stay rich.

 

[AcesandEights]

I bought a junkyard D30 back in the day and put it on some jack stands. I could take it apart and play with the internals all I wanted. It's pretty cheap and you get to sit there in front of it and really look all the pieces over as you disassemble/reassemble.

 

[Some Random Guy]

I bought a junkyard D30 back in the day and put it on some jack stands. I could take it apart and play with the internals all I wanted. It's pretty cheap and you get to sit there in front of it and really look all the pieces over as you disassemble/reassemble.

How much did you pay? I haven’t considered buying one to experiment on.

 

[AcesandEights]

@Some Random Guy Hmmm, seems it was $150 or $350. It was years ago now. It was relatively inexpensive. It was a high pinion D30 with 4.10 or 4.11 if I remember right.

 

[Some Random Guy]

Update: it turned out to be the diff was incorrectly set up by Randy’s Worldwide (Yukon Gear). I’m going to try and get them to fix it, but their warranty does not apply to oversized tires. My worst case has been realized. Dump another $1500-$2000 into this axle or upgrade at significantly higher cost.

 

[Some Random Guy]

Update2: They’re going to look at it. If it is apparent they made an error, they’re going to warranty it anyway. If they believe my tires lead to the failure, they’re offering a significant discount on the repair to make it easier to stomach.
I’m fairly happy with that compromise. Common sense escaped the boundaries set by the lawyers, I’d call that a consumer win.

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