Archived Rebuilding My Diff??

[Pull'nOld Iron]

Well at 85K my rear gear gave up the ghost. The timing couldn't have been worse. I lost my job on the 12/31 and the opportunities look pretty slim for now.



Anyway when I got it towed to the local shop, that has a good reputation, I got the bad news. It seems the axle bearing cap popped a bolt and let everything shift out alignment. This caused such a noise :--) $730 dollars worth. The gear was almost as noisy as the kitchen when I delivered the good news.



I looked at the rear end with the shop tech and I need a ring, pinion and new bearings. At this point the carriers look ok, but the speed sensor ring gear has a few teeth that are pretty narled up.



DO I need a new one?? I'm wondering since this doesn't mesh with anything and it should still pump out its sensing to the pick up unit. Any ideas here.



But my real question is; can I change this out myself and save the $$$$. I have rebuilt engines before, but have never even thought of dealing with gearing.



Any good sources for heavy duty parts at a good price. I tow a gooseneck with about 13K worth of old tractors on it, so it will get some use / abuse.



But if this Dana rear end will require shiming or dial indicator adjustments, I need to have the pros do it. I suspect.



Specs

99 2500 4x with 3:54 limited slip gearing. If more infomration is needed post particulars and I'll provide. I need to save wherever I can on this one. Momma needs a new dryer, oh my ears, my ears. :-{} :{

 

[Joseph Donnelly]

Your Ram has a Dana 70. Parts are readily available from places like 4 wheel parts 800-421-1050 or reider racing, etc. Junkyards have the stuff too, but just check that the usual 35 splines are on the diff axleshafts you find, if taking such parts. The housing of course has special mounts welded to it for the Dodge. If a carrier cap broke, I would definitely check the housing. You can get a new cap, but must mike it's ID to be sure it is round. They are select fit. The housing with caps installed is bored, so every cap it a bit different. Check the Dodge service manual and TDR#24. Your companion flange may be different from whatever you find in the boneyard. Dana 70s have been used for decades. . .

 

[Pull'nOld Iron]

Thanks

I appreciate the infomration Joe, thanks.



At this point I don't expect to change the cap. It does not appear damaged. But for some reason the bolt snapped, hhmm. I don't have a dial indicater but hopefully my calipers will surfice.



Do you think a back yard mechanic can tackle this job? I do take my time with things and make sure of what I'm doing. But as I related, no experince with gear setting.



Thank you for your response.



Take care

 

[Joseph Donnelly]

Some can. Some need a little help/checking from an expert. I recommend you read the two references--Dodge manual, and TDR24 before trying to decide. If you don't have that issue, you can get it from TDR, I think.

 

[danandamy]

just on option

Since money's tight, have you looked at any wrecking yards? You might can find a complete unit in a wrecking yard quite a bit cheaper. Then all you have to do is jack up the back of the truck and drop the whole axle out and roll the new one in. I know goin' in with new parts if everyone's first choice but sometimes you gotta do what ya gotta do when the $$ is tight.



dan

 

[JFinke]

You will need a dial indicator to set backlash. Also needed will be a good dial reading torque wrench to set propper pinion preload. It might possibly be done with a caliper that will read depth, but I wouldn't suggest it. You will also need a bearing puller and press so you can install and remove the pinion and carrier bearings as you shim them. It will be a pain getting the pinion set right without a pinion depth guage. If you do it yourself make sure you get a good contact pattern, especially on the drive side. If it's not right your gears will howl and eventually EAT themselves. You may also want to pull the rear end on your first ring and pinion job so you can stand up to work on it. It will probably take the better part of a day to get everything shimmed right. Whoever does the R&P make sure you break it in properly. Jake

 

[Joseph Donnelly]

Harbor Freight has magnetic bases and dial indicators cheap. They work fine. The DAna factory gear sets have the pinion depth marked on them. If the new pinion has a number two digits off from the old one, you change the pinion shim thickness by 0. 002". This process is described in the Dodge service manual. It avoids the need for a pinion depth gauge. When checking the drive pattern with yellow lead, put some drag on the ring gear by pressing on it with a rag on your hand, and turn the pinion. Even so, the pattern will be farther to the light load end of the drawings than what the manual shows for light load. For example, if your pattern is not to the inner edge of the ring gear, it never will be under load. It should just go to the edge of the gear by this method of checking. Under real loads, the contact pattern will spread out as it should. In contrast, the coast pattern will be more like in the manual, not all the way to the edge.

Good luck.

 

[jrobinson2]

Do you need a case spreader to remove the ring gear on a dana 70? or can ya cheat? Do you need a spreader on a dana 80?

Jared

 

[JFinke]

You can cheat. For the most part they are a convenience. If you do need one they can be home built with some basic fabrication. A spreader is only needed to get the carrier back in, because of the preload. The main time you use them is on differentials that use the shims for backlash/preload between the case and bearing race. Usually the shims, races, and carrier can be put in all at once. It would be nice if they built all pickup differentials with removable carriers and preload nuts threaded into the case/cap like a Ford 9". They are much easier to set and you do it with a holding fixture at the vise. Jake

 

[C Schomer]

There wasn't much preload left when I pulled mine out with a little prying. Going back in was much tighter. It took two people. One to hold it in place and the other with an oak block and big deadblow hammer. Craig