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

[1SLwLS1]

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).

The 4 link control arm bushings? I agree they're a weak link in factory form. When those act up, which should be soon (but hopefully I can make it to next summer), they will be replaced with Core adjustable arms and bushings.

 

[1SLwLS1]

Just picked up the truck from the shop, the noise is gone. I asked him if there was anything specific that was wrong and he said it was just a well worn unit, nothing in particular. He didn’t do a deep dive as we were replacing it all anyway. Pattern looks great and he said backlash was 0.006”.

Gotta change the oil in 500 miles with mineral based 85w-140, obviously no friction modifier, and two more easy-drives/heat-cycles and we can see what she’ll do. It’s gonna suck not getting to drive my usual speeds on the way to work tomorrow.

 

[danielmid]

Just picked up the truck from the shop, the noise is gone. I asked him if there was anything specific that was wrong and he said it was just a well worn unit, nothing in particular. He didn’t do a deep dive as we were replacing it all anyway. Pattern looks great and he said backlash was 0.006”.

Gotta change the oil in 500 miles with mineral based 85w-140, obviously no friction modifier, and two more easy-drives/heat-cycles and we can see what she’ll do. It’s gonna suck not getting to drive my usual speeds on the way to work tomorrow.

Is that the TruTrac? I can't tell from the photo. If so, my TruTrac is very happy with Red Line NS 75w-140. The NS doesn't have any limited slip additive. I changed it at the 500 mile-ish mark and haven't looked back.

 

[1SLwLS1]

Yes sir, TrueTrac. I will have to do more research on the mineral vs synthetic, I found an old BITOG thread with good information. I’m sure they were fearing synthetics with friction modifiers and reducing bias ratio. We’ll see which way I’m swayed after more research.

 

[Wild one]

Yes sir, TrueTrac. I will have to do more research on the mineral vs synthetic, I found an old BITOG thread with good information. I’m sure they were fearing synthetics with friction modifiers and reducing bias ratio. We’ll see which way I’m swayed after more research.

Tru Tracs manual says to use 85W-140 Mineral gear lube.I've got close to 600 passes and 50,000 miles on mine with mineral lube,and it's still working as good as the day it went in.They do say you can use synthetic,but they don't endorse it,as it can be to slippery

 

[danielmid]

Tru Tracs manual says to use 85W-140 Mineral gear lube.I've got close to 600 passes and 50,000 miles on mine with mineral lube,and it's still working as good as the day it went in.They do say you can use synthetic,but they don't endorse it,as it can be to slippery

Close, I read it as they don't test with synthetics and don't want to.

Add to that my lockup is smooth and I'm not sure what else I'd be getting from dino oil over the synthetic, and I trust the synthetic oil much more at protection and longevity.

 

[Wild one]

Close, I read it as they don't test with synthetics and don't want to.

Add to that my lockup is smooth and I'm not sure what else I'd be getting from dino oil over the synthetic, and I trust the synthetic oil much more at protection and longevity.
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I think it might also have a bit to do with your application to.If you're putting a bit more power down,and running a drag radial or slick ,you can potentially have issues in the water box.Just a daily driver basically stock truck is probably okay with synthetic,but they don't like synthetic in a water box,lol.I think as long as you stay on top of your diff maintence and change the fluid regulary,i don't think there'd be any noticable differances in wear between the 2 lubes

 

[mdc1990zr1]

I think it might also have a bit to do with your application to.If you're putting a bit more power down,and running a drag radial or slick ,you can potentially have issues in the water box.Just a daily driver basically stock truck is probably okay with synthetic,but they don't like synthetic in a water box,lol.I think as long as you stay on top of your diff maintence and change the fluid regulary,i don't think there'd be any noticable differances in wear between the 2 lubes

I had a G80 in a lot of my GM trucks. It is a locker and not a limited slip. Eaton was the manufacturer and they recommended mineral gear oil, not synthetic and certainly no limited slip additives. This was a mechanical locker whereas the one in our Ram 1500's are electronic. I think ours may be the electronic version of the old mechanical G80. I wouldn't be surprised if Eaton was the manufacturer.

 

[jr27236]

Had pretty much the same noise although NOT as bad as yours. Mine basically sounded like a baseball card in the spikes of my bicycle. This started after a long haul pulling mine close trailer with two large ATVS in it. I went through everything on the back , I started with rotating the tires, no difference. I then pulled the wheels back off. Off checked all the brake even the emergency brake to make sure they weren't rubbing. No difference. I then cracked the case even though I did the service at 80,000 mi and the fluid was fine. And then did the outer shaft bearings and seals put everything back together with new fluid again and no difference. At that point. It was time to bring it to a professional because I was not messing with that gear pack on a 392 limited slip. Turned out the culprit was pinion bearing race was all worn out from the bearing. Good thing now is I have all new bearings in the rear, even the inside shaft bearings.