From- http://www.quad4x4.com/Dodge%20Rear%...t_Upgrade_Kits

Dan the Gear Man™ Service Tip: Differential bearing failures are very common on trucks with Cummins Diesel engines. I recommend a complete rebearing job on these axles every 125,000 miles to prevent catastrophic failures. This is especially important with the Model 70. If cost is a major factor, you should at a minimum, replace the differential bearings and shims.


Well, mine lasted 115k miles. I feel the PO had it serviced and no one put the friction modifier back in the rear diff and all the material was worn off the clutch plates.

 

339K worked miles (kind of worked if u call 4500 pounds of ice, working a cummins dually) Original trans, original motor, original rear.
The rear has developed a little play, but sure aint toasted!

 

Mine ran 352,000. Most of good local shops say that's about the life of the bearings in these axles. (shops in my home town, not Indy)

 

Ive got 500,000 km (300,000 miles) on mine now and have developed some play. now when I let the clutch out there is a loud ping coming from my driveshaft. Time to overhaul. I have another 70 with only 15,000 miles on it so I am going to take the guts out of it. I guess I better rebearing it first.
Anyone know a thread on how to replace the guts on a dana 70? I know the basics but want to make sure i get all the little things right.

 

Mine made it to over 400K with 33's and then some 35's for a while and lots of pump mods, HX 35, POD's and a 5 speed. Lots of towing ( was a hot shot rig for about 275K of its life) and I still towed a lot till I got my 2nd gen. When it went it blew the power lock in half. too much power and too much load.

 

i just bought mine (150k km) and a carrier shim had come oud so there was a pile of metal on the cover magnet so i put new bearings all around including the axle bearings and put in a power lock lsd

this is a link to a dana factory manual covers the 60 series front and back but procedures are the same for a 70 ....make sure you pre load your carrier bearings http://coloradok5.com/dana60manual.shtml

 

Guys who rebuild rears only see the broken ones. Mine's fine at 250k - and mine hauled a GN around the Southwest for 200k before I got it.

 

Hi,
Mine now has 391000 miles on the original. I tow a 30' 5th wheel and my equipment trailer. Sounds and works great.
Mike

 

My 70 gave out at about 180k miles. I have another 70 in it now, but recently bought an 80 to put in it. I think it needs a pinion bearing first though

Eric

 

Thanks for the link, looks good.