Whining/Growl Noise - Differential/Wheel-Bearing/Transmission (output shaft)

[1SLwLS1]

Well since you have a 2wd, now would be the perfect time to drop in a TruTrac and regear if you wanted to, that way the entire rear diff gets rebuilt anyways. Trying to see some silver lining lol

That's the thought process. I have 3.92 gears now and running 2500 RPMs at 90 MPH is a bit high, I don't think I would want to change anything unless I decided to make significantly more power and need to change to a lower/taller gearset. I think I would rather just try to win Cleetus' Trackhawk giveaway.

Out of curiosity, is there a driveline shop in your area? Ask around there usually is in various areas ...and most people don't ever hear about them. They usually work on large trucks, dump trucks, driveshafts, things like that all day every day. Working on a pick-up is like a toy to them compared to commercial vehicles. They can usually pop out a pick-up's rear diff in blazing speed and get right to the root of the problem. (or do your upgrade).

Or a 4x4 Jeep shop is where I ended up for mine, they were fantastic.

Texas Auto Gear is a well renowned local-ish off-roading shop that was pre-selected years ago for differential work.

 

[danielmid]

That's the thought process. I have 3.92 gears now and running 2500 RPMs at 90 MPH is a bit high, I don't think I would want to change anything unless I decided to make significantly more power and need to change to a lower/taller gearset. I think I would rather just try to win Cleetus' Trackhawk giveaway.



Texas Auto Gear is a well renowned local-ish off-roading shop that was pre-selected years ago for differential work.

That Trackhawk sure looks fun, wonder what the retail cost is of all the parts he's dumped on it. Also the rims and tires look too small for my taste, but it's a clean truck that will put a hurt on almost anything on the road.

 

[1SLwLS1]

More than I would care to dump in I'm sure. All of those suspension components did not look cheap, plus the ported blower. Maybe he will give away the whippled f-150 next...again...

 

[1SLwLS1]

Well, it’s looking more and more like a well worn rear end.

Sloppy Rear Diff - 1

Sloppy Rear Diff - 1

youtu.be

Sloppy Rear Diff - 2

Sloppy Rear Diff - 2

youtu.be

 

[Wild one]

Well, it’s looking more and more like a well worn rear end.

Sloppy Rear Diff - 1

Sloppy Rear Diff - 1

youtu.be

Sloppy Rear Diff - 2

Sloppy Rear Diff - 2

youtu.be

Time to upgrade it to a true trac /new gears and bearings. With the power you're putting down,a true trac is a wise investment

 

[Jeepwalker]

Seen worse. I can see 'play' in the spider gears.

I still don't think you've found the 'root' problem. It sounds like a wheel bearing ..or some bearing is 'catching'. Can you remove the axles and repeat the test, rotating the center? Maybe there's an outer axle bearing race that's shot?

How did the U-joints look? And how did the tranny-side feel?

 

[Wild one]

Matt Fikac at Moes has the tru tracs with or with out master install kit.

Detroit TruTrac Differential for 9.25ZF Rear Axle

Detroit TruTrac Differential for 9.25ZF Rear Axle

www.moes-performance.com

 

[Jeepwalker]

If you plan on taking it to Tx Auto Gear, or another local shop, it might be a good idea to get a price from them on a TrueTrac ..or whatever you want to put in there (plus a rebuild). Unless they're cool with guys bringing in their own parts. Maybe they are, IDK. But a lot of shops have a hard time putting a warranty on a job when 3rd-party-purchased parts are involved. Esp a primary component. They have no legitimate recourse to go back to the mfgr if a problem occurs, and then things can turn into an uncomfortable finger-pointing match what parts were at fault. And in a differential, when things get messed up, oftene nobody can say definitively it was this or that part. A warranty ...the way you use it is probably worth having.

Some smaller hard parts I've bought in the past at a local driveline shop were actually cheaper on parts than the internet (when ya factor in shipping), and parts store.
.

 

[danielmid]

If you plan on taking it to Tx Auto Gear, or another local shop, it might be a good idea to get a price from them on a TrueTrac ..or whatever you want to put in there. Unless they're cool with guys bringing in their own parts. Maybe they are, IDK. But a lot of shops have a hard time putting a warranty on a job when 3rd-party-purchased parts are involved. They have no legitimate recourse to go back to the mfgr, and then things can turn into an uncomfortable finger-pointing match what parts were at fault. I'm just speculating ...it might be worth a ph call. A warranty on a diff ...the way you use it is probably worth something.

Some smaller hard parts I've bought in the past at a local driveline shop were actually cheaper on parts than the internet (when ya factor in shipping), and parts store.

The Jeep shop I used beat Moe's price by just a little bit and no shipping cost.

 

[1SLwLS1]

The transmission side and driveshaft felt fine but I think I am going to let the local shop take a look.

I just drove it down the block and yup, noise is still there with the new outer wheel bearings. It does it with the **** end lifted so at least I know it’s nothing in the front.

I am going to call shop tomorrow and see how they want to proceed with diagnosis but I am well aware of the headaches with customer provided parts, the torque converter I received while doing the 8 speed swap was for an 8HP75 and was a pain with everyone going around. With that said, I will get a quote both ways, I know of a few other cash discounts as well.

 

[Jeepwalker]

Yeah, I'd like to know what kind of $$ rebuilds are going for these days.

Cheers

 

[1SLwLS1]

Didn’t have a chance to talk to shop today but wanted to capture noise under vehicle and make sure it was rear axle related and not transmission related. Definitely rear axle.

Diff Whine - 1

Diff Whine - 1

youtube.com

Diff Whine - 2

Diff Whine - 2

youtube.com

 

[Jeepwalker]

Yep, sure sounds like it. You're wise to deal with it right away, before things were to melt together...

 

[1SLwLS1]

I have a feeling buying a used axle will be the cheaper of the two but I’ll update once the shop has time to diagnose and quote.

 

[mdc1990zr1]

I have a feeling buying a used axle will be the cheaper of the two but I’ll update once the shop has time to diagnose and quote.

When I had to rebuild a Chevy rear with the G80 it too would have been a little cheaper to get a junkyard rear, but I knew my rear (it was hit on the passenger tire by a car momentarily stopping that wheel and damaging the rear. I chose to have the rear rebuilt at the local Chevy dealer and it was a good job. Rebuilding your rear eliminates a lot of "unknown" problems that could rear their ugly head and you will have to live with the outcome. Just my 2 cents.

 

[1SLwLS1]

I am just going to look at the difference in cost and see if that justifies a truetrac.

 

[Wild one]

I have a feeling buying a used axle will be the cheaper of the two but I’ll update once the shop has time to diagnose and quote.

For what you're putting through the diff with a cammed 6.4,you'd probably benefit from a tru trac.If that's the case you might as well rebuild the diff you have. Have you ever thought of sticking 3.21's or 3.55's in the truck,first gear and 3.92's with your combination is probably virtually useless as you'd blow through it from tire spin before the truck has moved. The A8 392 cars only use 3.09's as their deepest gearset,anybody drag racing a 392 car is running the same size 17" drag radials as you would be

 

[1SLwLS1]

I’ll look into it some more but with the pig of a truck (full weight crew cab with stereo) and some sticky tires, I don’t think 3.92s would be all that worthless, but I’ll dig a bit deeper.

 

[1SLwLS1]

I just got off the phone with the guy and he wants to look at it and see what all it needs but he is saying worst case (assuming nothing wrong with housing, just internals) with a new gear set and Truetrac differential, it is about $2,100. That is only about $600 more than a heavily used (142K miles) assembly from LKQ, shipping not included - really only about a $200 difference with tax and shipping. Seems like a no brainer but will attempt to get a proper diagnosis from shop so I can post here for others more inclined than myself that may want to tackle this on their own instead of just upgrading everything.

 

[Jeepwalker]

Given the way you push the truck, might not hurt to have them check the bushings while they're at it, and replace them. Good chance they're not super tight. I've noticed a couple control arm bushings on mine which seem kind of loose (and it's been relatively baby'd).