Dana 70 rebuild.

[1stgen4evr]

rebuild by a 'novice'

Well JD, that is what I think. But read everything here and get the manual and read EVERYTHING there and decide. The blue is part of the job. If you understand preload and can follow the manual as to getting the contact pattern, you can do it. With slack in the pinion, you will most certainly need to do a complete bearing set. The contact may have to be a happy medium if it has been run long with slack in the contact. When you open it up, if there is scuffing on the gears from low lube, you may need to replace the gear set as well. If there are metal flakes in the bottom, observe the caution of CLEAN CLEAN CLEAN. Lot of good mechanics won't tackle the job. That doesn't mean it can not be done.



Remove the cover and tell us what you see.



1stgen4evr

James

 

[MMiller]

James;

I'm not sure you want to know how I put my carriers back in! When I have had danas apart, I have always got the carrier out with a little persuiasion from a pry bar, working the sides out. Ususally when they come free unless they get cocked in the housing they will fall out on you and pinch what ever body part between itself and the ground! I will shim mine up to get the wear pattern and backlash appropriate, check carrier endplay. Add the endplay to the amount of preload, and add the appropriate thickness of shims. I then put the cups on the bearings and get it up to the housing. I then use a soft face dead blow hammer to persuade the carrier back it. As I am doing this I keep checking that the pinion is not binding up, so I know the pinion is not holding the carrier from going in to the housing. With this procedure I know I am getting a little preload on the carrier bearings, because the housing will not fall in or out. If it does not go in without using a hammer excessivly then I deem it too tight.



The gear ratios we mess with on our trucks are all in all pretty forgiving(3. 55-4. 10). When you start getting into your 4. 88-5. 13 then it is a little more tediuos. Mainly because the pinion keeps getting smaller, contact area is smaller, and when gearing that deep, you know there is either very large tires, large motor or both involved.



Just so everybody knows, I do swing wrenches for a living, working on Cat Ag equipment. I assure you if you are confident enough to rebuild a engine, swap a cam, or clutch, with patience and a good book, a r&p replacement is possible. Heck if you can read a book, follow instructions, and ask questions when nesessary, you can work on diffs.



Michael

 

[1stgen4evr]

To JD and all the contributers

If you decide to go for it, start with safety first. Don't know how you are set up as to work place and shop tools. You will need to get the truck up so that you can convienently work under it. Be that a full lift or jacks to get the back up. You will want to have GOOD stands under the frame and let the axle drop to the extension of the springs/shocks. I like to have enough room to sit under in a position that has my head level with the center of the axle. At least enough that I can move in or out without cracking my noggin.



Hand tools will get the carrier out but an air wrench is mighty helpful with getting the pinion nut off. There will be lube on everything you own and all of your body parts if you don't prepare for catching it when you pull the drive axles and open the differential. You will need three times as many rags and catch vessels as you first estimate. As you remove things, mark everything as to left/right up/down. Tiny marks with a punch will help. (The carrier caps are bolted on to the housing and then bored with the assembly. They are specific as to side and top/bottom.



As/if you disassemble the carrier, be even more positive as to where everythings goes back. Count the shims. Tie them in sets. Mark them as to location.



Don't be intimidated. Sounds like you only have a wear condition to correct. If you suspect that the axle may be distorted, there is a post back a while on that and some discussion on how others have check for the problem. As Michael stated, if you can build an engine to close tolerence, you can do the r/p.



Again as to safety, the carrier will seem to leap that last dab and smack the he** out of whatever it can. You need a friend under there with you. Use some method to catch the carrier and not chop a finger. I have certainly had to do the reassemble with a soft face dead blow hammer. Try to find a spreader. It makes the job so much less painful taking out or going in.



If you are going to be the test subject, I will certainly try to answer whatever question you come up with. No doubt the other guys will jump in as well. I know for a fact that more folks would do this job if there were a source and confidence factor on their side.



OK guys, what did I miss.



1stgen4evr

James

 

[JDMills]

James,

I will report back whatever I find, as it is, the truck is not with in reach, but it should be soon. thanks for your response and encouragment.

Jason

 

[REakin]

Originally posted by 1stgen4evr





As to the general owner, would you think they should shoot for "tight" or "middle" on preload spec. While I lean toward tight for the very reasons you suggest, as long as you are "in spec" you are safe. I am wondering what to state if this gets as far as a FAQ. My goal is to have more people do the job themselves. It is a *****in job but if they will get their head into the process, they will get it done.

I think that everyone should shoot for the tight side of the specks. The only exceptions that I can understand would be on a truck that I fear won't get a proper break in, a truck that MUST be driven a long distance (over 30 miles at interstate speeds) before putting 500 miles on the new setup, or a off road only truck (it won't ever see the miles or heat for proper break in).



For the beginner: I would suggest pulling the axle out of the truck and getting it up to at least belly height to work on. Being your first time you want to take everything slowly and be careful about everything you do. I know it sounds like a lot of extra work to do but it should only take you an hour to get out and an hour to get back in. EVERYTHING about the setup will be easier if you are comfortable. I can remember nights in the garage under a truck up and down, up and down, up and down... ... Pull the pinion, knock out the race, add a shim, knock the race back in, out, in, out... UGH!!! I'm only 22 and it hurt ME! This can be an agravating job, so if your the impatient type just pull it out. It will save you hours worth of agravation, Your back will thank you too! And hey, it never hurts a truck to replace the U bolts!



Look at your pinion yoke and be sure you don't have a grove worn around the seal surface, if you do have a groove: polish it out on a lathe(<-- Only for VERY light grooves!!), get a new yoke or find a speedy sleeve that will work. It's not going to do you any good to have to find out you have a leak later. Fix it NOW!



Take your time and do everything right. Take it appart and clean it up! Pull the housing out and take it to the carwash! Clean it all out! No old should go in with the new! Nothing good can come of it! Play with the pinion untill you can make it mesh perfectly with the ring gear. Backlash isn't as important as some people make it out to be. The meshing pattern is the key to a quiet ride. I can think of three instances with aftermarket gear sets that I had . 014" backlash and a perfect pattern and . 009" with a half assed okay pattern. ( one Dana 70 and two 10. 5"-14 bolt's) (one of them is in my toyota) Go for the gold! ( I wouldn't go beyond . 014" though... . ) Agter your happy with your patterns get the bearings snugged up to the tight side of speck. just do it. break it in right. you be happy man! LOL!!





When it all goes back togeather Locktite the **** out of the pinion nut!



I need to go... ... I keep talking about breakins..... Maybe I share my method with you? maybe I don't.....



I guess I will if anyone's interested. Lather though... .



Rob

 

[1stgen4evr]

I will if anyone's interested.

Hey!!!! If we are going to do it tight, we need the secret stuff as well.



Spill the beans.



Thanks



1stgen4evr

James

 

[CGauthier]

Great thread James If my diff needed a rebuild I think I would have the confidence to at least try it with you guys around-although I'd probably be just as nervous as i would be if i were stranded alone in a tropical rainforest with a shirt that says "eat me" lol, ok not quite that bad But, when I changed the diff oil this spring that was the very first time i've even looked inside a diff... If Dodge would ever get that manual in that I ordered in February I'd be willing to give it a shot with help like you around, good job



Thanks for the info,



Carl G

 

[REakin]

Re: I will if anyone's interested.

Originally posted by 1stgen4evr

Hey!!!! If we are going to do it tight, we need the secret stuff as well.



Spill the beans.



Thanks



1stgen4evr

James

All right then. First thing is to run it with no load at all. Leave the truck up on a GOOD set of jack stands. This is the best time to find out if you messed up! Start the truck and run the axle at about 10 - 15 MPH for 2-3 min. This will make sure that you have lube flowing into all the bearings. You did put gear oil in it didn't you? Set her down and go for the first test drive. You want to run it for 10 - 15 min. Easy on the go pedal! Drive 30 to 40 MPH. Park it and crawl underneath and feel the cover. It should be warm to the touch but not hot. If you didn't get her warm go drive it again. If she's warm then you let her sit till she's cool.



When she cools down, go drive her the same 10 to 15 min at 30 to 40 MPH again. Let it cool. Again. Cool. Get at LEAST 100 miles on her like this. I usually shoot for closer to 200. It gets really boring though! Just think of all the trouble free miles you are making for yourself though! ( The neighbors will ask what in the hell you are doing, they always do!)



The idea here is to get the faces of the races and the rollers to start and take each other's shape. Yeah they look the same but I'm talking on a microscopic level..... The last thing you want to do is go out and get the thing scalding hot in the first 300 miles. What will happen is the races will get hot spots that will wear differently than the spots that were cooler. Makes for a rough bearing... . and well.....



After you get tired of driving around slow, you can kick it up a notch. I like to get on the interstate and run about 65 MPH for about 10 to 15 miles. Crawl back underneath and put yer hand on her now..... Little harm huh? if you burned yourself you drove too fast or too far. Let it cool down again. Go, cool, go, cool, go, cool. After 300 miles a 40 minute trip at 65 won't hurt anything. Got 500 miles yet? no? keep going! After 500 I change my oil. I clean out all of the old oil that I can. Use brake cleaner, carb cleaner or the like. Clean off the inside of the housing, the cover. Don't clean out the bearings though, you'll do more harm than good. Don't ever run bearing's dry. Bad, bad! Fill her up with fresh lube and drive it like you stole it! but no heavy loads until you break 1,000 miles. Change your oil every 15,000 miles on a truck that get's used. You could go longer but oil's cheap and putting bearing's in that pig was hell wasn't it?





Rob

 

[BSchindler]

REakin; Great break in advice. Real similar to the way we break in precision machine tool spindles.

 

[1stgen4evr]

putting bearing's in that pig was hell wasn't it?

So with all the encouragement from every one, who will be first to try it? I was looking at one of the Haynes manuals for the trucks and the advise there was that since this is a job for seasoned mechanics, they don't include the procedure for bearing replacement. And not a word on matching contact on the R&P. But the info IS available.



Well, most of the guys with first gens now are at least better than shade tree grade oil changers. If you have not run anything to destruction and you are wanting to reshim, take the next step. After you have read the procedure from a complete manual and with the info in this group of post, put you questions here and lets see if we can talk you into it or through it. Installing a new R&P is a bit more involved but not too much.



I have to say that I really like Robs method. Pretty much all of it. If you can't take the axle out, I can attest that it can be done under the truck. You could ask my son about the knot on his noggin as to whether you should make the effort to get it out from under the truck. Another reason is that you can check out the spring group if you have any sag on either side. If you have a broken tie bolt, that will show when you unbolt the springs. And you are going to keep the truck for ever, right?



While I can attest that you can get the carrier in and out without a spreader, it sure makes the job LOTS easier. If you can not find one, go with Michaels advise.



Now when you get to the breakin part and get antsy and rush the procedure, don't whine to Rob about it. Do it right. I would inject here that the reason I will use old bearings is that they have already run in and can be put up 'middle" preload and put back on the road right away. You had better know what you are looking at if you are going to use an old bearing however. Considering the reasonable cost of new bearings and the proven method to break them in, I still lean toward all that Rob has posted.



You will join a select group of mechanics when you have completed the job correctly.



I will offer this as a FAQ after we have a couple of success notches on our belt. Or maybe just run the whole group of posts.



Thanks Thanks Thanks

1stgen4evr

James

 

[MMiller]

Looks very good james. A whole bunch of good info in this thread. I can attest that my FSM does have the info of setting up a r&p. I am sure that chiltons etc do not. Tommorow I will once again be testing my work on the rear end, and also be testing my getrag! All hooked up grossing around 21,000, gonna go do some truck pulling.



Once again at the end of a thread like this I am really glad to be a part of the first gen group.



Very good work guys,



Michael

 

[dpuckett]

WOW Lots of good info and details here. This may take differential work off my "I wont mess with it" list. Then that would leave pumps and injectors, though I am not completely ignorant of what the inside of a VE looks like.



Question. Let's say you get your bearings on the carrier, do your preload, and you end up with too much backlash in the R&P, but good contact marks. Do you have to take the bearings off the carrier, and effectively move the bearings over? Taking a shim off one side and putting it on the other? Or does it even make a difference? And what does the average Joe (or Dan :-laf) use to apply the load to the carrier to establish load contact patterns?



Also, when I go to a 3. 54 (on my current carrier), will I need to start from scratch? I. E. have to do the preload for the bearings again, and get the offset just so? OR does the 3. 54 ring gear not need to be moved over to match the bigger pinion? Bearings have 40K on them now, so I'll reuse them.



I'll have to reread this when I fart my backside off my shoulders- I've been in a gloomy funk all week, and just not real absorbtive (sp?) of the material presented here.



-DP

 

[dan brooks]

Originally posted by dpuckett

Question. Let's say you get your bearings on the carrier, do your preload, and you end up with too much backlash in the R&P, but good contact marks. Do you have to take the bearings off the carrier, and effectively move the bearings over? Taking a shim off one side and putting it on the other? Or does it even make a difference? And what does the average Joe (or Dan :-laf) use to apply the load to the carrier to establish load contact patterns?

If you have too much backlash your pattern should be off, too... . at least, that's what I saw based on my experience. I don't have my FSM handy, but I think the pattern diagrams shown differ based on too much/too little backlash and pinion depth.



The placement of the shims - both pinoin depth and those between the carrier and carrier bearings - will affect the pattern. As far as preload goes, we set up a dial indicator to measure side-to-side movement, then added about . 015" worth of shims over what it took to get the pattern right with the carrier snug. With the extra shims in place, a soft-faced (plastic or leather) mallet was used to get the carrier in place.

Originally posted by dpuckett Also, when I go to a 3. 54 (on my current carrier), will I need to start from scratch? I. E. have to do the preload for the bearings again, and get the offset just so? OR does the 3. 54 ring gear not need to be moved over to match the bigger pinion? Bearings have 40K on them now, so I'll reuse them.

You will need to set the pinion depth and backlash with a new ring and pinion, but if you're reusing the same carrier you can just move the shims side-to-side to get the right pattern.



I'd strongly suggest buying a master kit (new pinion and carrier bearings/races, shims, ring gear bolts, Loctite, marking compound) if you're changing the ring and pinion. Odds are you will damage the shims when removing the carrier bearings (you can measure them and build a new shim pack with new ones in the master kit). Also, make "set up" bearings out of your old parts (hone the inside of the bearings so they slide on and off with minimal effort). Odds are pretty slim that you'll nail the set up on the first try, so the bearings will be coming off at least a couple times. One thing I learned: seat the "set up" bearings well to compress the shims. I had everything dead on using my set up bearings, but when I pressed the new bearings on I wound up with too much backlash. Turns out there was a taper on the carrier that kept the shims from sitting flush when putting the bearings on by hand, but pressing them on compressed them several thousandths more.



This all sounds pretty intimidating - I know it was for me - but once you start doing it things will make more sense. The FSM is an excellent source of info, but most of us don't have all the special tools they call for. We did my axles with only a dial indicator and stand, micrometer, and bearing puller/separator - most of which was bought at Harbor Freight. Round up all the parts and tools ahead of time, read the FSM a couple times, and then give yourself an extra day or two to get the project done - if it takes longer than anticipated you're covered. If it takes less, then you have time to start breaking in the gears before you start working them.

 

[MMiller]

I agree with dan. Use your old carrier bearings to setup the new gears. Just open them up a little bit. Heck the bearings were only about $30 for the carrier.



When doing setup, I turn the pinion by hand and put my other hand on the O. D. of the ring gear letting the ring gear slide past my hand, just to make some drag. That way my pinion is getting good contact to the ring gear.



Michael

 

[REakin]

Re: putting bearing's in that pig was hell wasn't it?

A good source of information is "Randy's Ring and pinion" They advertise in the back of fourwheeler, 4 wheel and off road, some hotrod mags... ... They sell everything that you could need for an install. They also have a very detailed set of instuctions. The only thing to watch there is their gear sets. They get some pretty cheap gears in there. ( yukon, some US gear sets..... ) Go for spicer gearsets. Precision gears made in factory gear ratios are actually repackaged spicer gears. Use Timken bearings.



As for pulling out the rear end, just do it if it's your first time. Don't even think about doing it under the truck. The exception is if you have a rack or a pit to work from. If you don't your just going to **** yourself off, hurt your head, back, elbows, neck and who knows what else. Plus if you take it out you can have it sand blasted and paint it to look like new! ( If you do have it blasted be sure to tape up your spindles and leave the cover on and get a plug for the breather!!)



It's really not a hard job. It just takes the right tools, some time and some patience.

























and maybe a few good buddies with some brews.....

 

[1stgen4evr]

Good buddies and brews

Put the brew on ice and save it till you have the pattern. After that it is time to celebrate. All the rest is nuts and bolts.



Thanks Rob and thanks to all who made this post. I am just the facilitator here. Had a couple of inquirys on PMs. If anyone feels that they have the time to offer counsel to a first timer let me know here or PM. I think I can walk anyone through the job but I want the first timer to have a second opinion. After we have gotten a couple of successes, I will include a report as to questions from first timers and then petition Bushwhacker to put the entire post on the FAQ list.



I expect to be doing mine some time next week. I will only do what I have to to get the backlash and preload in spec. I realize that may be more than I think right now.



1stgen4evr

James

 

[JDMills]

May be this is a bit too much for me to tackle... Had I not known what was involved, it would be easy to start and then have to finnish. I have yet to get the truck back so that I can pull the rear cover will be asking for advice soon after that depending on what is found.



I agree this is a great thread, I may be willing to try and set up a ring and pinion on my 46 WDX as a result, especially since it is more of a toy, than a work truck. Thus repairing the repair is not such a irritation.

Jason

 

[1stgen4evr]

This info humbly submitted. I believe Timken tapered roller bearings are held to very

Going back to BShindlers previous post. Would everyone know how to use a couple of parallels and micrometer to check the length of the bearing stacked, thereby having a length reference?



You could use these numbers to determine the shim difference in the old bearing and the new while figuring in the previously determined side play in the old setup. This asumes you used a puller that didn't destroy the old bearing and measured the side play before taking the carrier out. With these numbers you might see that you only need to replace the bearings to eliminate the slack.



1stgen4evr

James

 

[1stgen4evr]

repair info

Browsing the net I found a couple more sites that have some good info on doing diff repair. If you don't have a FSM manual, there is good info on the tools needed and the contact pattern.



http://www.imajeep.com/axles/differential_repair.htm



Also www.completeoffroad.com has tools listed and replacement gear sets. These guys have a video put out by Richmond Gear on the repair.



1stgen4evr

James

 

[dodgenstein]

New source for Nylock spindle nuts

I came across a new source for the factory style nuts and wedges. I found a nut and wedge from Dorman parts at a local shop. The part numbers are:

Nut Dorman #616-335

Wedge Dorman #616-336

Listed application as Ford 350 series van or truck 1981-1987. Didn't have time to get a price, but has to be less than Dodge or Dana/Spicer.