Mutt Diff, Reparable or Junk?

[Lou]

Found axle side of diff was leaking. Found this after removing it for a reseal. Somehow do not believe a new seal is going to fix this issue!

Have not had a mutt diff apart in 15 years. From what I remember the splined shaft that goes into the carrier has no bearings. So I believe the carrier and shaft are worn out. What do you folks think?

And yes, checked the bolt is not loose and the yoke is ok, the actual shaft has this play

https://youtu.be/qs4Xmv_MvCo

[svramselaar]

hi

take a look at the top of this page the first topic

[rickf]

hi

take a look at the top of this page the first topic

George, were you talking about this?
viewtopic.php?f=3&t=4863

Lou, if it is not the yoke on the spline then it is probably the spiders.
Here is a rebuild kit.
https://tnjmurray.com/5702185kit-spider ... a1-a2.html

[svramselaar]

Hi

Yes Rick
This is it it sits above hit own topic
He can take the other side flance and see if it is the flance spline`s or the spider axle
Otherwise take it apart only the sidecover off and see
If he is careful there is no adjustment needed

George

[Lou]

Thanks for all the feedback about the diff issue. Created a video showing the play is in between the carrier and the axle shaft. The play is so excessive, the axle seal cannot flex enough and that is why the seal was leaking.

My opinion is that a spider gear repair kit will not fix this issue. There are no bearings inside the carrier that the axle shaft rides in. My belief is that even with a new axle shaft installed, the carrier will be worn and there still will be play. The axle shaft is hardened steel and the carrier is not, which do you think is going to wear first?

Amazingly, both plug magnets have no metal in them and the drained oil was clean. There appears to be no excessive play in the spider gears, and the play between the ring and pinion appears fine.

So without a NOS carrier available, it looks like the Diff is considered a disposable item. Have any of you folks seen this failure on a Mutt before? If this is a rare failure, is it possible it was an out of spec axle or carrier and over time both wore out do to wallowing from excessive play?
https://youtu.be/UZcBMSSeyIs

[svramselaar]

hi

take it apart you have nothing to loose
three U joints and three bolds and you have it
the pinion shaft must not out
look where the problem sits
is it at the bold on side cover you can put a busching at a workshop
a other diff is a lot of money i see them for $ 550.- till € 700,- at the net

george

[rickf]

I have a pallet load of diffs here, Not sure how many are good. But I have never seen one fail like that so you might be able to steal the carrier out of one of these and put it in yours.

[Hambone]

I would get a used one and put new seals in it, I see them on the cheap often, or go get one of Rick's, he will never use them.

[rickf]

Nope, I will not. Unless I start rebuilding them.

[Lou]

I have a pallet load of diffs here, Not sure how many are good. But I have never seen one fail like that so you might be able to steal the carrier out of one of these and put it in yours.

Really appreciate your offer and insight. However after reviewing the link on this group for the rebuild I do not have the tools to set it up. By the time I purchase a dial type inch pound gauge and a micrometer set up, would be a good ways to owing a NOS diff. I tried to clamp the diff in my vise, and was a no go. Now I know why the author says to use an engine stand.

Even if a nos carrier was found, still would need a set of shims and the tools. Diff's are now twice the price I paid 10 years ago. So in 10 more years a nos diff will be over $1,000. So then if a nos carrier is found it would be worth rebuilding it, so will hang onto it for a possible future rebuild.

[Lou]

I would get a used one and put new seals in it, I see them on the cheap often, or go get one of Rick's, he will never use them.

Will not take a chance on a used diff. Look what happened to this NOS diff with only 10,000 miles on it! Reliability is very important as Meg and I go deep into the woods where most civilian vehicles cannot fit because the trails are so narrow. That is why we keep so many spare parts in the mutt. Where we go we are pretty much on our own, rarely seen anyone unless they are on a motorcycle, even that is rare.

Concerned about diff failures, had a diff in a 67 T-bird fail. The spider gears blew and locked up the diff. When you tried to move the vehicle, one wheel was turning right and the other wheel was turning left. Can still remember how much the axle was twisting when I tried to move it. Had to have the vehicle towed.

If this happened in the middle of the woods we would be screwed. Cannot pull the driveshaft out as all the oil would leak out the transmission. Wish I could weld, seriously thinking about fabricating a transmission driveshaft yoke with a bearing on the end. Connect a bracket to the bearing and connect it to the trans somewhere, hell even a ratchet strap would work. All the bearing and bracket have to do is hold the empty yoke in so the oil does not leak out. Then can drive home with the front drive train, like we did when the axle blew up last month.

As long as the diff did not lock up could always pull the axle shafts off if the spiders failed like above.

[Mark]

As a temporary fix, put the front differential in the rear, remove front half axles?

[lpcoating]

I had an NOS diff fail at about 2,500 miles on the first day of a 3 day road trip. We did what Mark suggested. To get the truck to where we could work on it, I pulled the rear half shafts and engaged 4wd. The rear diff obviously still rotated but was not under load and we made it to where we had to get. There was nothing fun about it but we were able to do a fix and continue the trip for a total of 549 miles. When I returned I installed 2 NOS diffs in the truck. Hopefully these hold up better than the last one.

Guy

[Lou]

I had an NOS diff fail at about 2,500 miles on the first day of a 3 day road trip. We did what Mark suggested. To get the truck to where we could work on it, I pulled the rear half shafts and engaged 4wd. The rear diff obviously still rotated but was not under load and we made it to where we had to get. There was nothing fun about it but we were able to do a fix and continue the trip for a total of 549 miles. When I returned I installed 2 NOS diffs in the truck. Hopefully these hold up better than the last one.

Guy

Can you please tell me in what manner your diff failed? Did the spiders lock up in the manner I described above with my T-Bird, Or some other type of failure?

Had a NOS diff fail after 3,000 miles, but it was Jerry's fault who used to work for TNJ. He said to fill the NOS diff with 100% Lucas. Well it was so thick the spiders did not get lubed in the carrier and the thrust washers failed. He did not make good on it had to spend for another new diff.

DCP_0727.JPG

[lpcoating]

About an hour into the trip, rear diff became incredibly loud and hot. Pulled over and it was literally smoking. Very metal on metal sounding. I'll check the flanges but I don't remember any excessive play. The date on the box was 1989 as I remember.

20210603_160447.jpg

Guy