rear axle, fix or forget it.

[ARhine]

Took apart the D70 last night



Both cups have spun in the housing and the bearings on the case evidently since it has spit some shims out.



The housing has some groves in it, as do the caps, but not terribly bad.



Have not pulled the bearings off the case yet to see what it looks like.



The side and spider gears are also worn and mesh sloppy.



214K on the axle.



Found a D80 in a 98 model year truck 3hrs from here for $650 with core is my other possibility. Has 114K miles on it , might not be any better?

 

[steved]

I'd forget it... get the D80 if you can swing it... you will have well over $350 invested in the D70 rebuild and new center chunk (open carrier) anyway. More if the ring and pinion have been damaged.



If those caps or the housing have any imperfections, it can cause misalignment and problems soon down the road... and most likely the carrier is junk too... once they spin, it is difficult to prevent it from happening again.



IMHO, get the D80 (make sure it isn't hurt)... the D80 is just plain BEEF over even a D70. If you do deside to resurect the D70, get everything as smooth as possible... then epoxy (like JB Weld) all the races and cups in, this will help hold everything in place... been there did that, still holding up 100k later.



steved

 

[HRDROKN]

Just completed the rebuild on my D70... I had the PowerLok bearing journals welded and machined for $150. Rebuilt the PowerLok $100. New carrier bearings $70. Took . 001 off the bearing caps to tighten them up. I will also be installing a bearing support girdle in a couple weeks. Some picks at: 83 Crew conversion

 

[ARhine]

I am trying to find a good thread on the D80 swap. Not coming up with alot so far.



What I have found is that the Ubolts need to be different, the spring plates are spaced farther appart, and I will need to redo the shock mounts. Anything else if I decide to go that route?

 

[TKingsbury]

Another thing I'd check is the overall width of it from axle flange to axle flange (where the wheels bolt on). If it is much wider than what you have, your tires will stick out a bit. Check with RonA, he put an 80 in his truck. Check his readers rigs album, maybe there's some pics.

Travis. .

 

[ARhine]

I called them back and I think I got them talked in to measuring it for me.



The don't want my D70 as a core and want $750 with no core.

 

[dan brooks]

My D70 spun a bearing and spit some shims from one side of the carrier, and the other race spun in the housing. We were able to save it by shaving the bearing caps and used Catapillar "bearing lock" (extra strong loctite) on the carrier bearings. It has held up to 40k+ miles so far, with a lot of that hauling a camper and/or towing the Jeep on the trailer.



I was fortunate that my ring and pinion weren't damaged by running with the excessive backlash, but with 214k miles you probably won't be so lucky. If you have to do a total rebuild, the D80 would probably end up cheaper in the end.

 

[mysteryman]

Dana 80 retro fit

I saw a 90 dually while I was in Florida 2 weeks ago..... It had a Dana 80 in it.

It seemed to fit perfectly... It had the correct 72 to 92 12X3 brakes and hubs on it. The drive shaft angle looked correct as well... The owner said that he ordered the axle new from a Dana distributor and had a shop install it ... ... He said that he paid 1600. 00 for it 6 years ago... . He was not very informative past that... . I could find out if Dana has an axle that is a direct bolt in as a stock item if there is some interest... I am sure I could order some if they are not a shelf item but

they are going to require a quantity order...



I myself do not think that I need anything any better than a 70... I never overload my truck nor do I have the hp turned up very much.....



I never much cared for Dana (spicer div) axles ! I thought the way they shimmed the bearings was a cheesy cheap way of doing things. They should have had threaded adjusters on the differential bearings like we had on our 8. 25" and 9. 25" axles had...



Another engineer friend of mine speced an axle for his D350 last year. . It is either a Rockwell or an Eaton. I can't remember now. I will have to give him a call and ask him to send me a copy of the spec sheets and see how practical it is... He tends to over do things a bit at times. .



Back when these trucks were under development we did design a 2 spd rear axle for them. . It was never produced or used because of cost ... . What a shame ! it was real cool !!!



Let me know if anyone wants me to look into any of this any further

 

[ARhine]

I don't like dana's setup either.



I have also considered regearing the front to 3. 73 and putting a GM 14 bolt in the rear. Easy to find, strong, and MUCH easier to setup with spanners and a removable pinion assembly.



Mechanic I know sugested the locktite method as well. Guess I could try that route and see how it goes first. Would be out the money for bearings and labor if it didn't work out.



Also got a call back with the measurements on the D80. Looks like a match. The other thing is they said it has disc brakes so it must be newer than the first salesman told me.

 

[steved]

I am trying to find a good thread on the D80 swap. Not coming up with alot so far.



What I have found is that the Ubolts need to be different, the spring plates are spaced farther appart, and I will need to redo the shock mounts. Anything else if I decide to go that route?

If you hunt a D80 hybrid (found in the 2500 HO and 5spd/6spd trucks up to 02), then it is almost a direct bolt in... single rear wheel, axle tubes are the same as a D70... ubolts would be the same. They put a true D80 under the 3500s, the D80 hybrid was found under a lot of 2500 trucks... in simple terms, a hybrid is a d80 center chunk with D70 outers (tubes/axles/hubs/brakes).



Or find another D70, I had over 200k on mine with no issues (I did rebuild the posi, but that was it)... you are talking a 0. 5 inch larger ring (10. 5 to 11), and slightly larger bearings... I believe the biggest difference between a D70 and D80 is the cost of parts... D80s are EXPENSIVE... parts are almost double what a D70 cost... I don't think that strength is increased very much.



A 14 bolt is a good option, eventually one will find it's way under my M37. Simple, strong, cheap, and very common... about the hardest thing would be shocks and spring mounts... you can buy a new yoke for the pinion to match your driveshaft ujoint... and speaking of driveshaft, changing rears might require shortening/lengthening the driveshaft... if it were mine, I would seriously consider this, even if it is a GM truck piece :-laf . You can get them drum braked, disc'd, or buy a kit to convert to discs also.





steved

 

[ARhine]

I have a 14b setting in the shop. It is loaded with 4. 56 gears and I am doing a disc conversion on it from greatlakeoffroad.com . It is going under my rock crawler though. I can pick them up for $100 each all day long. Common and easy to find around here. Now the D60 front going into the same rig I had to pay some cash for.



A 14b is just such a better design it is not even comparable. No pressing bearings on an off to set them up, no need for case spreaders, ect. .

 

[steved]

I have a 14b setting in the shop. It is loaded with 4. 56 gears and I am doing a disc conversion on it from greatlakeoffroad.com . It is going under my rock crawler though. I can pick them up for $100 each all day long. Common and easy to find around here. Now the D60 front going into the same rig I had to pay some cash for.



A 14b is just such a better design it is not even comparable. No pressing bearings on an off to set them up, no need for case spreaders, ect. .

And detroits are cheap too!



steved

 

[TKingsbury]

Just as an aside, Strange Engineering makes a "Super 60" now. It is redesigned with threaded carrier bearing adjusters and is a 100% new piece. Wont really help anyone here with a stock diesel truck, but I thought some of you/us that deal with other stuff might be interested.

Travis. .

 

[1stgen4evr]

"Back when these trucks were under development we did design a 2 spd rear axle for them. . It was never produced or used because of cost ... . What a shame ! it was real cool !!! "



Not just cool but super cool if it were available. Did you do a prototype? Most drivers would kill the thing I guess but I sure would love to have one.



James

 

[ARhine]

well, from what I can find on the web the newer axles have a WMS (wheel mounting to wheel mounting) measurement of 70" Is this right



The guy at the salvage yard measured from disc to disk, not the wheel flange and got 63". I told him I wanted WMS but he didn't do it.



A little over 5" more than the 1st gen SRW axle? I don't know if I want my tires out around 2. 75" farther on each side in the back or not.



Guess I am just going to have to unhook the stock trailer and pull my dads 02 in the shop to pull the back wheels off.

 

[BushWakr - RIP]

Psssstt... ... . detroit... . detroit locker... . sweet !!!



pb...

 

[mysteryman]

yes we made a proto type

"Back when these trucks were under development we did design a 2 spd rear axle for them. . It was never produced or used because of cost ... . What a shame ! it was real cool !!! "



Not just cool but super cool if it were available. Did you do a prototype? Most drivers would kill the thing I guess but I sure would love to have one.



James

 

[steved]

well, from what I can find on the web the newer axles have a WMS (wheel mounting to wheel mounting) measurement of 70" Is this right



The guy at the salvage yard measured from disc to disk, not the wheel flange and got 63". I told him I wanted WMS but he didn't do it.



A little over 5" more than the 1st gen SRW axle? I don't know if I want my tires out around 2. 75" farther on each side in the back or not.



Guess I am just going to have to unhook the stock trailer and pull my dads 02 in the shop to pull the back wheels off.

I could see this... the 2nd gens have some serious wheel offset... like 5inches of backspacing or so... I don't think the 1st gens have that much.



IMHO, the 14bolt would be the route I would go if I couldn't find another D70 that I could rebuild. I believe the 14bolt will also be really close to the WMS to WMS measurements you need.



steved

 

[ARhine]

More info:



The front D60 in a 89-93 W250 is 67. 5" WMS measurement.



This means with a 2nd gen D80 in the rear it would only be 1. 25" wider on each side in the rear than in the front. Mabye it wouldn't be so noticable after all?

 

[TKingsbury]

Like I said, RonA has one in his truck. His tires are out further than they should be, not horrible but he has stock tires/wheels too. If you have wide tires it will be very noticeable I'd think. By the way, I replied to your post on Pirate. I'm Crashnzuk on there. I've done some measureing at work and found the 14 bolt in the older late-model Chevy trucks (88-99?) are 65" wide too. I would think it would be real easy to find a good one and slam it in.

Travis. .