Rear end troubles

[jdalexa84]

So I opened up the rear end on my truck to change the diff fluid and the carrier is badly marked from the pinion grinding against it. It is an open 12 bolt with 3.07. So my question is what could be the cause of this. I am not very experienced in differential work.

[cdowns]

40 or so years of hard use causes a problem like that

[jdalexa84]

So the carrier having grooves ground into it from the pinion rubbing it is most likely just from worn out parts? Could it be an improper application of parts?

[Mike C]

It's because the pinion nut has come loose either presently or in the past. When you accelerate, the pinion is pushed towards the front of the truck, when you decelerate, it is pulled towards the case and if the nut is loose, the pinion eats into the case.

[jdalexa84]

Guess its time to get a new carrier. Ring and pinion look ok and the internals look good as well other than the pin that goes through the spider gears. Any suggestions on where I can buy a new one. Not looking to spend a ton and I'm ok with the open rear end

[68 P.O.S.]

Perfect time to add a posi and deeper gear!

[hamjet]

If the reason you opened it was to change the fluid, and not because it was acting up or making noise, then check the pinion to see if its loose or if anything else looks fishy. if you don't see any chunks of metal in the bottom of the case then maybe it had a problem in the past and was corrected. Fill her up and keep on truckin! (other than the pin that goes through the spider gears.) Whats wrong with the pin?

[Shaky]

If the backlash is OK, and the torque on the pinion nut is OK, and the ring-and-pinion look OK, I'd clean out the housing as best I could and put some new fluid in. Check it in a year to see how it's doing.

[Mike C]

Like the other guys said, if it checks out OK and the damage is from a previous failure, just refill and drive.
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[snipescastle2]

I have a stock, open carrier I'd be happy to send you for the cost of shipping.it originally had 3:73 gears, but now its just a carrier- spider gears/cross shaft/shear pin. Let me know.
Ben Smith

[jdalexa84]

Any idea what years are interchangeable with these trucks. I like having the 307 gears, I'm not looking to tow or race and like the idea of getting better mileage. I have a junk yard near me that list any carrier for $86 so I will most likely go get one there and if I'm lucky I'll find a posi. Thank you for the offer for the carrier but I don't think my gear set will work with it from what I understand. And as far as why I opened it up, I bought it from a friend and it had been sitting for a few years and figured it needed changed. The truck isn't on the road yet still putting it together.

[jdalexa84]

Pictures of the carrier

[88Ironduke]

Wow, I don't think a cleaning and refill is going to help! Your description of "badly marked" doesn't exactly describe that damage.

Paul

[jdalexa84]

That is why I posted pictures wasn't exactly sure on how to describe the damage

[hamjet]

How does the pinion look? Was there any chunks laying on the bottom or was it clean. if no signs that the pinion did that damage then it must have been changed. I'd put it together and use it 'if it were mine' as long as it wasn't giving any problems earlier, unless you can get one for a reasonable price locally. ( as I said, if it were mine )

[67 chevelle]

Thats more than a "scratch" ,, Id replace it

[Mike C]

If the pinion is not really hammered looking, I wouldn't worry about it. But if it makes you feel better to replace, open carrier used is pretty much a gimmee item. Now a good time to consider upgrading to a limited slip.
Posted via Mobile Device

[hamjet]

I blew up the pic and looked at the ring gear closely, it looks like the ring gear has been wearing wrong, it must be the original one. doesn't look good, ( unless I'm seeing it wrong) only you can see it better. I think I would change it after all..

[jdalexa84]

When I felt the pinion it had sharp edges but no chunks out of it. It is an original gear set from 72.

[snipescastle2]

here's a few pictures of the Carrier I have, just to show the condition of it.... of course, you will want to replace the bearings when you go to reinstall it, also, I couldn't find the C Clips, you can reuse your old ones.
Ben

[Redline novdog]

With that much metal in the oil, your oil would have looked like bass boat gel coat. your bearings would/should have been toast. Unless that is old damage since repaired.Check your bearing fits. if that is old damage run it!

[davepl]

Ouch. The rear end on my brand new Z06 with 500 miles just went... hope it's not as broken as yours!

[hamjet]

Bummer davepl, too much power? should be covered, right?

[davepl]

Originally Posted by hamjet

Bummer davepl, too much power? should be covered, right?

Thanks, it will, but they are on national backorder. If there's no realistic chance of it locking up I'll drive it till it dies. I don't know if they go from howling to breaking or just howl louder or what eventually happens... anyone?

[Tony]

I do some differential work and that 12 bolt looks a bit beat up. but nothing that new gears and bearings won't fix..