Rear Axle Woes - Looking for some advice

[EricB]

Hi all


I sold PFP on eBay last weekend, and told the buyer I'd do one last thorough check of the whole truck before its departure to its new home on the East Coast.
Well I opened a bit of a can of worms for myself when I decided to re-pack the axle bearings with fresh grease - it had been on my to-do list for a couple weeks ...


Driver side axle came apart fine.
Removed the four nuts that hold the drum backing plate to the axle housing, and the driver side axle slid right out.
I counted 3 shims in between backing plate & axle housing.
With the castle nut and special washer removed, the axle bearing slid easily off the axle by hand (no press needed)
Checked everything, cleaned everything out, re-greased and re-assembled with no fuss.

I pulled out the differential, cleaned out the case, looked it over, and since it passed muster, reinstalled / resealed the rear cover, and filled it with fresh gear oil - no issue there either.



The passenger side axle has been something else altogether though.

When I first pulled the drum off, but before I loosened the four nuts that hold the drum backing plate to the axle housing, I noticed there was some in/out play on the axle - grabbing it by the wheel studs I could get maybe 1/4" of back and forth movement when really there shouldn't be any...
I uploaded a video here: http://www.ericgbauer.com/IMG_1506.MOV

With the four nuts that attach the drum backing plate to the axle housing removed, I had to give it a hard tug to have it come loose.
(This was already different behavior than the driver side)

I also counted three shims (totaling 0.040") between drum backing plate & axle housing

With the passenger axle completely removed from the axle housing, I first noticed that there was only one single rib of threads showing above the castle nut - on the driver side there was 3-4 ribs showing with the castle nut tightened on...

IMG_1515.jpg

Then even though the castle nut was tight against the bearing, I could move the drum backing plate 1/4" in & out before the bearing sat flush in the bearing race the way it is supposed to be.
I uploaded a video here: http://www.ericgbauer.com/IMG_1512.MOV

When I tried to disassemble the axle I found that the axle bearing was not budging - it did not slide right off with the castle nut removed the way it had on the driver side.


I thought that maybe because so few threads were showing above the castle nut that maybe the bearing wasn't seated all the way down on the axle the way it is supposed to be.
My trusted machinist was slammed with other work and couldn't help so I went elsewhere.
I asked the other guy to try to press the bearing IN to see if it would budge - it didn't and the bearing cracked.
He removed the dead bearing while I ran all over town to find new axle bearings.
When I got back he wasn't done removing it, so I dropped off the new bearing and had to leave.

-> I should have stuck around and baby sat him <-

When he called me back later that afternoon, he had removed the old bearing and pressed the new one in.
He was unable to tell me if for sure there was a spacer underneath the race - I bet he didn't check even though I asked him to.
And the result is that there was just as much play in the axle as before - the new bearing hadn't done anything to cure the problem.
It was 5pm and he was closing up shop and literally pushing me out the door.

I went home, re-installed the axle just to see and confirmed that there was no difference from before.
The problem this in/out play creates is that the drum will hit the backing plate which is no bueno of course.

I pulled the axle back out and this morning went to my trusted machinist who now said he would make the time for me.
He has it now, he's going to remove the new bearing and call me over before he does anything else.

He thinks like me that perhaps the spacer that is supposed to be between the outer seal and the race in the drum backing plate is not there or damaged.
If he has to he will machine a new one for me.




Based on this description do any of you fellow Patrol'ers have some ideas to share?
I've been exchanging emails offline with Leslie & Rob already and they suggested I post this up for everyone to look at.

Incidentally and just to be on the safe side I did also post a WANTED Ad for a passenger side axle in the greater SoCal area which I would be willing to drive out and pick up if it comes to that ...

PFP is supposed to be loaded up on its eastbound transport on Wednesday of next week so the clock is ticking ...
Any and all help is greatly appreciated as always!


The new owner has been super cool with all this and understanding.
He really wants PFP so that's great to hear!

Thanks everyone

-e

[mad4hws]

Hi Eric,
I know at one time last fall, Specter OffRoad had some Patrol Axles. I was looking for some, but they were too much to ship back east. fingers crossed I might have a set of axles being shipped to me in Connecticut soon. If I do, I will have extra parts. Not ideal, but if the buyer is close to my location, I might be able to help if all else fails.

[Esteban]

Eric, I have revised the videos, although very rapidly. Also read your description.

Rest assured, you're not having any problems with your axle.

The way the axles setup work, is that they touch the tips inside the differential. When the two axles are in, if you check the play there's going to be little because the opposite axle is preventing further move. But once you remove one axle, the other will move freely in and out the amount you have described. To properly setup the axles, both need to be inside, and then you start checking the end play, and adjust it with the shims.

After a lot of use, the tips of the axle that rub each other will wear a little bit, and to compensate that, you have to normally remove shims to compensate. The axles rub each other only when you turn and the rotation is different between the tw. When going in a straight line, they rotate together and no wear develops.

I will not be concerned about the amount of exposed thread above the axle nut between the two axles.

The idea once you figure out the end play is to have somehow equal amount of shims on both sides.

[EricB]

Hi Esteban

Thanks for the info, one thing I don't understand though is the following:

With the castle nut tightened on the driver side there is no in/out axle movement when the axle is off the truck.
With the castle nut tightened on the passenger side there is 1/4" of in/out movement when the axle is off the truck - as shown in the second video I posted.

I understand what you are saying about shims, but I don't understand why the axles would behave differently when they are both off the truck.

If I add up the total amount of shims I have it is maybe 0.080" / 2mm
So even if I moved all the shims from driver side and added them to passenger side I would still not take up the amount of slack I am seeing.



Hi mad4hws,

I'll call Specter when they open this morning.
Thank you for the offer but I want to hope it doesn't come to that.

-e

[Esteban]

With the castle nut tightened on the driver side there is no in/out axle movement when the axle is off the truck.
With the castle nut tightened on the passenger side there is 1/4" of in/out movement when the axle is off the truck - as shown in the second video I posted.

I understand what you are saying about shims, but I don't understand why the axles would behave differently when they are both off the truck.
-e

I doesn't look right as you mentioned. Guess I rushed watching the videos. I looks as if the spacer is missing as you noted. Hope all of this clarifies when you get the new bearing installed out.

[Flaggoni]

I just retrieved the axle assemblies from my boneyard Patrol. They have not been disassembled in 25+ years. Both sides have about one thread showing outside the lock nut. They both have approx 1/8 to 3/16 inch of in-out movement when not installed in the axle housing.
Mild Bill

[EricB]

So we found that the bearing spacer was slightly cocked on the passenger side, thereby not allowing the bearing to sit all the way down where it needs to be.


So we're all good now ...
Thanks to all