I agree that welding the gears for anything but a gofast stait vehicle sucks!

Check your oil for a metal hue to it! Changing your diff fluid is a great idea anyways!
It will tell you what's going on like your engine oil.
When I lost mine it made a slight wine groan above 30 mph. Its slowly got louder before I could figure it out! It took out the pinion gear and thrustwasher(I that's what its called)
I drive the crap out of my truck! All the time... Pretty much exploded the clutchpacks and the metal in the oil wore other things and bam 2k$

eaton detriot are the best, unless you want a air/electric/ cable locker! For the rear I feel its a waste jmo. The front its worth it! if its money than a stock replacement is a great option! You get used to driving with a locker! Not many options for the 80, but I did find great deals on ebay!!!

As for doong it yourself, unless you have someone to help you who has done it before! Spend the money to have it done. Nothing sucks more than having your truck down for more time! And it happens quick most of the time!!!

 

dont weld them like mentioned...that's the cheap mans version of a spool which belongs on vehicles that never touch the road...get a limited slip and skip the locker...you dont need it unless you and romping it pretty hard offroad (or lifting tires) all the time...limited slips will do everything you've mentioned...also skip on the stock unit and pick up a good aftermarket ls...as mentioned, detroit true trac...best one out there in my opinion plus it doesnt use those little plates like the others, thus, you dont wear it out...pay for the labor and unit once and never worry about it again

 

Actually there is a long thread over on TDR about restacking the rear diff clutch packs. It seems that when DC built the truck they didn't stack them the way they SHOULD haved been (you know Friction plate,clutch plate,friction,clutch and so on) but stacked them so that they wouldn't grab as hard to cut down on noise complaints and so on.

If you already have an LSD you can go out and buy new clutch packs (I believe Randy's R&P has them) for around 200. Dodge wants over 500 for em so don't go there! However they offered 2 different positracs in Dodges. One is the Trac-lok the other is the powr-lok. I'm still confused as to which one had what but the only way to tell for sure is to pull the cover and look at the case. One has a V-shaped notch where the cross bar goes and the other just has a round hole.

I'll do some checking and get back to ya.

 

Clutch material is soft, it won't damage bearings or gears, you must have gotten it contaminated somehow, water is usually a good culprit, mud does it in a hurry.

Chrysler didn't build the D80, Dana did, I know, I worked for them... From the factory, all the clutch packs were done correctly (unless one snuck by QC). However, I have heard of guys rebuilding them clutch, steel, steel, clutch, steel, steel, clutch... etc. They claim it keeps the rearend from chattering. Its a cheesy way of not using friction modifier, and steel on steel can wear down and ruin rearends, but its unlikely.

Neither of the factory limited slips are great from the factory, even good is an exaggeration. If you have either one, rebuild it and live with it unless you really need a positively engaging LSD (like it could leave you stranded in the back country).

 

Guy's thanks for the info, i will get of my butt and get to tearin it apart to take a look inside to see what's up. It would aleast give me a reason to service it, the oil hasn't been changed in about 100,000 miles. But at least i don't drive it hard?

 

... I've said that before...

 

I have detroit trutracs in both my front and rear of my truck and they are worth the money. They have awesome road manners but lock up good off road i have put them thru hell on the pullin track and never have any problems and if i remember correctly i paid 550 shipped for each but i put them in myself so i didnt have any labor charge.

 

Underpressure when you put them in did you have to reset everything or did you just pull the ring gear and bolted it to the true trac and put it back?

 

You'll want to measure your backlash before you take it apart and then set it back to that after you put it back together. You'll want to check the contact pattern as well.

 

You HAVE to check GTP (gear tooth pattern), backlash is also critical if you want the thing to last. Not sure of the exact specs on the D80 (its been a while), but I believe Backlash has to be between 6-10 thousanths, but it might be 8-12, either way, if you're at 10, you're good. As for GTP, you'll need some gear paint (its more like thick grease), a brush, and some brake cleaner to get the gears clean before you apply the paint. If its off, you need to get it right by shimming it.