Archived Rear Axel Shavings

[LandShark]

Rear Axle Shavings

I'm in the middle of a fluid change and found about a tablespoon of shavings attached to the magnet. Some are an inch long and 1/4 inch wide. Also found the usual (less than 1/2 teaspoon) amount of fine iron sludge stuck to the magnet. Bottom of the differential was clean. Jacked up the rear end and spun each tire in both directions and didn't get any noise or binding. Never had shavings in prior changes. Just over 160,000 miles on truck, 3. 54 gears, NOT anti-spin.





Any ideas on what is going on? Anything else I should check while the cover is off?

 

[Dieselnerd]

Those look like remains of your preload shims, probably not shavings. I would guess your center section no longer has a preload. You may also have spun the bearings in the caps. Pull off the bearing caps to check. You will see a groove in the bearing cap if the bearings have spun. If they are OK, while you have the caps off, see if the center section is loose in the case. Try pulling it towards you, it won't come out with the axles still in place but you should get an idea if it's loose or not. You should not be able to move it if you still have some preload. If it's fairly tight, clean out the debris and refill it. If it isn't howling, you can probably get by for quite a while yet. If you don't feel qualified to mess with it, just clean it out, refill and take to a good rear end shop. Chances are the only thing you will need are carrier bearings if they have spun. Some take the precaution of also replacing the wheel bearings at the same time. That may or may not be necessary. There are a lot of better rear axle experts on this forum than me so expect some good replies. Good luck!

 

[LandShark]

Here's a better picture:

 

[LandShark]

I pulled both bearing caps. No grooves, but the left side has a mirror finish and the right has about a 220 grit finish. The center section can be pulled out about 1/32" and rocked side to side about the same.



I'll leave the cover off overnight in hopes I get more suggestions. I'm thinking that tomorrow I'll clean it up, refill with cheaper (non-synthetic) oil, (I usually use Mobile 1) and then pull the cover again in 1000 miles or sooner if I hear noise.

 

[ata]

Those are the pre-load shimes. There should be no movement at all in the carrier. This is a common problem with the D-70. All the torque load is put on the left side, because the ring gear is off-set to the left of center. If you keep running the rearend that way you will RUIN the ring and pinion and the housing.

 

[LandShark]

Thanks to Dieselnerd and ata. That's the kind of info I needed. I'll look into getting a rebuild done ASAP. Any ideas on parts and $$$ involved?

 

[Dieselnerd]

As long as the bearings are good you will just have to pay for some shims and the labor costs to have the preload set up properly. A good rear axle guy should be able to set it up in an hour or two as long as everything else is good. ATA is correct, if the preload is gone don't run it anyplace except the axle shop. Yours is gone, the center carrier should be unmovable by hand, you need a case spreader to get it out when the shims are correct. If there are no grooves in the caps the bearings are probably OK. The shop may dress the cap ends down a few thousands to grip the bearings better as long as they are not seized. If the carrier bearings are bad they run around $200 or so. Last ones I replaced were a few years back so they may cost a little more now.

 

[LandShark]

Thanks MYSTERYMAN, I have very little in the way of mods on this truck; just a 230/605 plate in stock position. I'm an exception on this site in that I never race and rarely use full throttle, or even half, and rarely exceed the speed limit. I do however haul heavy (GVW= 10,500) when my camper is on and that has been for about 50,000 of the 160k miles on the truck. About 1,000 of the camper miles are in 4x4 (mostly low) in mixed beach and mountain logging and mining roads. The rest of the miles are empty.



I will be looking for a good rear end shop here in the northwest and will not take any shortcuts. I want to keep the truck as reliable as possible.



Gee... ..... Maybe it's time to finally install a limited slip or locker?