How hard is it to change pinion and carrier bearings on a dana 70.Any suggestions on bearing suppliers?I have a cheap 20 ton press.

 

Hunt up a timken usa supplier. Buy from a dealer, they have been good in past. Some gear suppliers have kits avaliable and they have also been good.
Do you have bearing growl??? The job is not easy in my opinion. Sure don't want a diff shop to tackle??

 

pinion is getting loose. you can wobble the yoke by hand.

 

Pull the drv shaft off, snug up the pinion nut till the play just disappears, it's quick and dirty but works. I've seen the nut actually back of on other types of diffs

 

The Dana 70 doesn't use a crush sleeve, it uses shims to control pinion preload. Tightening the nut will only work if it has loosened up. On this model, you can't tighten it any further to compensate for bearing wear. New bearings and races would be in order.

 

Torquefan
Thanks for the clarification on the bearing preload! I'm guessing with the shim system vs crush sleeve, its not as likely for the nut to have backed off,
Dont these diffs require a spreader to get the carrier out?

 

True, on these, the nuts only seem to back off if there's wear in the yoke splines that causes play.

A spreader is definitely a nice luxury to have, but I've seen many professional guys remove and install them without. Usually, the bearings are so worn that they'll just fall out, then if the preload's right, they can be tapped back in with a plastic deadblow mallet. You eventually get a feel for the right preload by how easily the carrier goes back into the housing.

 

It may be unlikely, but it DOES happen. It's probably the easiest thing to check, and I'm all about doing the easy stuff first. Drop the Driveshaft and just CHECK the nut for tightness. Like Chicken Soup - it couldn't hurt!

 

This is about the easiest rear end to put new bearings in. Just cut the bearings off of the carrier with a cutting wheel and when you go back together just put all the shims back EXACTLY where they originaly were. Check your backlash just to make sure but bearing manufacturing these days is good enough that none of your settings should change. I rebuild about one a month at work in E350's. I can usually do the bearings and the posi rebuild in 3 hours or so but if you dont have much experience give yourself the weekend to dink around with it. And like these guys are saying torque everything or the pinion nut and cap bolts will back out.