Just replaced the rear end with a detroit locker. drove the truck about 5 miles and it was knocking again. replaced everything but the pinion gear, which looks fine. the truck stopped moving, had to engage it in 4wd just to get it home. took the carrier apart and a ton of metal shavings came out. all the teeth were chewed off on the locker. any ideas?

If you are talking the rear pinion seal, it isn't too bad at all. You just have to drop the drive shaft, remove the pinion nut and pull the pinion, then knock out the old seal and hammer in the new one. Going back together is just the reverse but you have to torque the pinion nut to the specified setting. As long as you are not removing the pinion gear you do not need to worry about setting the rear end up or worry about the crush sleeve.

your front diff may have a problem with to carrier gears if making noise each way left or right on a detroit locker front end they just make noise because of how it is made if it has a locker front end may be problem,have to open front case and inspect carrier either way.

Could be the pinion gear ,,Has it been leaking rear end oil? How many miles on this?Probly over a 100k? its old enough for it to start wearing out.Try changeing the rear end oil use Lucas.

If you take the VIN # to a GM dealer they should be able to tell you the original rear end that the vehicle came with. If you are going to take the rear end to a shop they will be able to tell when they take it apart. If it is a posi rear end it will have a tag under one af the cover bolts (if it has not been removed) Once inside a posi rear end is immediately identifiable from the clutch pack. Also the number of teeth is stamped on each (pinion and ring) gear. Divide ring gear # by Pinion gear # to get rear end ratio. Didn't get directly to your question, but I hope this helps. Let me know. Thanks

Yeah. Ring gear and pinions are a matched set. They both get replaced at the same time. You have to get the pinion depth and the backlash set properly also.

Sounds like the original wear pattern of the ring and pinion was disturbed when the pinion was tightened too much. Once a wear pattern is set in the gears you can't really change it. It might be the ring and pinion wearing that you are hearing and not a bearing at all. It's not the worst thing in the world but will cause the ring and pinion to wear improperly and is annoying. Differential work needs to be done by someone that really knows their stuff to avoid these little problems.

This would be a seriously long "how-to" to be answered on this forum. There are MANY tech articles written and posted on the web on how to change gears. There are specialty tools needed to ensure the correct backlash, pinion depth, etc. is achieved, the right thrust washers used, etc. The rear axle is a Dana. Any Dodge, Scout, Jeep tech forum will have this process listed step by step along with pictures. For an even better guide, pick up a repair manual for your Jeep at any auto parts store. The procedure, torque specs, pinion depth, etc. are all covered in great detail.

The simple step by step is: Remove drive shaft and diff yoke. Remove diff cover (have drain pan under it), jack up rear of vehicle, remove rear tires and brake drums, remove bolts holding axle bearing retainers in place and pull axles out far enough so they are not still in the carrier/side gears. Then mark the carrier bearing caps so you know which side they were on and which end of the bearing caps go up. (Need to put them back on in the exact orientation that they came off). Remove carrier with ring gear, remove pinion gear/shaft, replace pinion shaft/gear with 4.10 one. Replace ring gear with 4.10 one. Reinstall the reverse of removal.

There are many procedures that need to be followed during all of this such as using set up bearings to make sure the pinion depth is correct and that the gear pattern/mesh is correct. Bearings all around should be checked as long as it's apart. Best time to replace them is now if it's an 81. This is not a simple job if you have never done it. If you do not perform it correctly, the new gears will be toast very quickly. It can also be a safety hazzard.

Here are some forums.
http://www.quadratecforum.com/archive/index.php/t-69320.html

This one is installing a locker, but same concept.
http://www.myjeeprocks.com/feature/detroit-ez-locker-installation/

Here's a good jeep forum.
www.jeepsonly.com

this means the ring and pinion gear are worn, but when u do the gears u will need to also replace all the bearings as well.

Two choices. Find an axle assy from a wrecked truck, or if your ring/pinion gears are OK, install Detroit Locker TrueTrac to replace spider gears. Good luck.

The C/Tr: C refers to the colour of the vehicle Tr refers to the interior colour A/TM is your transmission type. None of those numbers identify the rear end ratio.

What you need to do: Since you have to replace the rear end, yank it out. Examine the ring & pinion gears on the differential carrier. Mark on each a starting point, and count the teeth on both the ring & pinion gears. Now, after you have both totals of teeth, divide the # of teeth on the pinion by the number of teeth on the ring gear. Example: 12 teeth on the pinion, 46 teeth on the ring
12/46 = 3.83 ratio