PINION BEARING QUESTION

[MIDNIGHT RIDER]

My rear-end is Dana 70 DRW.

How do I determine if a pinion bearing is worn??

I have been experiencing an annoying torque vibration.

All U-joints are new Spicer.

The transmission yoke is new.

All engine and transmission mounts are new.

I can wiggle the pinion yoke in it's housing, not a lot, but some.

Should the pinion be firm, un-wiggleable; or, is an amount of side-play acceptable??

Truck has several hundreds of thousands of miles on it.

The nut has never been off the pinion, since new.

If I remember correctly, the inner bearing is pressed on the pinion, right??

The outer bearing just slides on, right??

What size socket fits the nut??

If the outer is bad, the inner probably is bad, also, right??

Tapered, like a wheel-bearing??

Thanks.

 

[sle2115]

My rear-end is Dana 70 DRW.

How do I determine if a pinion bearing is worn??

There should be no play.

If the outer is bad, the inner probably is bad, also, right??

Not necessarily. The inner gets much better oil as it is right in the oil bath. The outer has to rely on oil being slung up through the housing/crush sleeve etc.

Tapered, like a wheel-bearing??

Yes, I believe it is a tapered bearing. Been a while since I have been in a 70, don't have one around anymore, but IIRC, they are a tapered bearing. I would replace the race too if there is any discoloration, but they can be a pain with the pinion in place.



There should be no play. I had to replace the outer on my dana 60 front and went to the trouble to tear it all down, which is a pain on the front end. The inner looked like new, the outer was shot!

 

[MIDNIGHT RIDER]

Not necessarily. The inner gets much better oil as it is right in the oil bath. The outer has to rely on oil being slung up through the housing/crush sleeve etc.

I am glad that you brought that to light; it makes sense.

I may just replace the outer bearing, at the present; as, less than a couple weeks ago, I drained and replaced the fluid; and, as best as I could ascertain, without removing the retainers, the side-carrier bearings were in good shape.

Can I even see the race, with the pinion still in there??

How, on earth, would I go about getting the race out, without removing the pinion??

Pour Coke on it and watch it eat it out??

Thanks.

 

[sle2115]

I have used a slide hammer with a hook on the end. I have one I made but OTC used to make a bearing puller attachment for their slide hammer, that is where I got the idea from. Yes, you can see it. Use a light to tell how bad it is. If it is clean silver metal you should be good. I would look for ridges as well, but make sure you wipe it off well. Sometimes the oil will make it look rough.

That being said, before I get flamed for telling you not to replace it, the standard disclaimer applies! It would be best to remove and replace it, but I have done it on my own vehicles and been fine for quite sometime. I would guess that the new bearing would not last as long as if the cone and cup were replaced, but if it gets you 4 or 5 years, that may be enough. I also pack mine with synthetic grease and use synthetic gear oil. I do the same with the wheel bearings and have had VERY good luck. I was told to do this by a Ford Service Manager of over 25 years, suffice it to say, he has done a few. He also has his own garage at his house where he works now, he has been doing this for some 15 years or so.

Anyway, if it were mine, I would look at the cup (race) and if it looks good, replace just the cone (bearing). Good luck.

 

[tonkadoctor]

I may just replace the outer bearing, at the present; as, less than a couple weeks ago, I drained and replaced the fluid; and, as best as I could ascertain, without removing the retainers, the side-carrier bearings were in good shape.

Can I even see the race, with the pinion still in there??

How, on earth, would I go about getting the race out, without removing the pinion??

Pour Coke on it and watch it eat it out??

Thanks.

Pinion should be tight, usually the first sign of a bearing going bad is a leaking seal.

You may as well get a ring & pinion installation kit as it will have the new carrier & pinion bearings, races, crush sleeve, shims, pinion nut, pinion seal etc... The gear installation kits are usually cheaper than buying just the bearings separatly.

Do it all at once and do it right and be done with it for another several hundred thousand miles. It's about a 5 - 10 hour job depending on tools & knowledge and having a buddy help out.

Worst part of the job is setting the preload on the pinion bearings and crushing that damn crush sleeve. It takes about 300 ft lbs of torque to crush that god awful sleeve so you can have a couple inch lbs of bearing preload.

 

[MIDNIGHT RIDER]

Does anyone remember the needed socket size for the pinion yoke nut??

As of the moment, my plan of action is to simply replace the outer bearing, and race if necessary; and, I will get serious about it when time allows.

I really don't have the time to completely overhaul the rear-end; and, I am looking for a disc-brake Dana 80 to rebuild and swap in.

I would rather spend the rebuilding dollars on the Dana 80, while it is out, and then, install the "like new" unit in the truck; then, I will completely rebuild the existing Dana 70, to have for emergencies.

If I were to lose a rear-end, a long way from the house, I could have the spare brought to wherever I am, install it, and take my time repairing the damaged rear-end.

Also, the pinion seal has had a slow leak from the first time I ever saw the truck, about twenty years ago.

It looks like a grease river; but, it only loses about a half an inch per year.

 

[tractorman86]

easy turbo!!! dont pull the rearend apart just yet!!!!! i had a vibration like that before, is it only while u are mantaining your speed? if so the first thing i would do is tighten the nut(cant remember what size tho) and see if that solves the problem. mine had never been touched for 15 years and came loose on me so for your wallet's sake check the nut first!!!!! GOOD LUCK!

 

[MIDNIGHT RIDER]

Mine came loose on me; so, for your wallet's sake, check the nut first!

I had one come loose at the other end, next to the transfer-case, on a 78 Chevy, with a trailer load of cattle.

I was cruising along, about sixty, when the truck starts this awful bucking.

I thought for a second that it was gonna wreck me.

The front yoke finally slid completely out; and then, the driveshaft commenced to beat the underneath to pieces.

The nut and washer were still trapped, between the U-joint and yoke.

I looked the situation over and thought I had got by pretty good, considering all the bucking/lunging that had been going on.

I proceeded to replace the yoke in it's rightful place.

Everything looked good and I hadn't spent a penny, yet.

I fired her up, to take off, and couldn't get it in gear.

I layed under the truck, while the wife worked the clutch; and, everytime she pushed on the clutch, a huge crack would open up in the bell-housing, and one ear of the transmission had broken off.

Let off the clutch and the crack would disappear.

It turned out that I didn't get by so good, after all.

 

[tractorman86]

man that's got to suck i got off reeeeaaal easy! all that happened to me is i had to tighten it up!!!!! it came loose enough to make one hell of a racket but all it did was the pinion rubbed on the carrier a little on the very end but all contact surface was unscaved, thank god!!!!!

 

[krawlr]

This is the procedure on a D60: http://www.pirate4x4.com/articles/tech/billavista/Gear_Setup I'm not 100% sure it's the same but I'd be willing to bet it is. A good education on the subject in general.

I've done a few D44s and a couple 60s and they all used shims for the pinion preload instead of a crush sleeve.

If you do have to pull the carrier and pinion out to get your cup out, be careful with your pinion bearing preload shims, it's easy to knock them off in the housing without knowing it.

 

[MIDNIGHT RIDER]

Mission accomplished, so long as I didn't tear up more than I fixed.

Socket size is 1-5/16".

No crusher-sleeve, but shims as stated.

Bearing and race looked as good as new.

There was slop and considerable end-play before disassembly.

I removed the thinnest of the shims to take out the end-play.

I put in a new $18 seal --- what a rip-off --- they were $6.77 at Advance if I would have waited for delivery, maybe tomorrow; so, I went with the high price at the other place, so I could get it done.

Upon reassembly, minus the thinnest shim, all slop and end-play is gone.

I tightened the nut as tight as I could get it; maybe it will stay.

I know that the proper thing is to use a new nut each time; but, not many experienced mechanics ever do.

The parts houses do well to maybe have the right bearings/seals, let alone stocking new pinion nuts.

I had to load a bundle of cross-ties, before the fork-lift man went home; so, I haven't had a chance to really see if I eliminated my annoying little vibration.

Thanks for all the valuable input on my project.

 

[MIDNIGHT RIDER]

Just for the record, the shim that I removed was .017 thick.

 

[gdhillon]

do you have any pics of this pinion bearing?