I got around to tighten the grooved nut on the pinion today. One thing which puzzles me though is measuring the torque it takes to turn the pinion. If I leave it a few minutes it takes a lot more torque to turn it, than right after it has been turned???

Brg,
Karsten

What are both readings??????????

After resting a little, maybe 20-30 seconds, it is 3.9 Nm, after it just has been turned it is 1 Nm.

There is nothing attached to the shafts, new bearings and seals. Both axle tubes are horisontal

The grooved nut has been tightend with approx 130 Nm

Brg,
Karsten

Is it cold there?? [heavy lube}

Spin it over a bunch of times and take a reading , then let it sit for an hour and take another
This is when it just starts to move, correct???

Around 15 deg cel. in the garage. The differential is drained from oil, maybe I should fill it up and excersise it as you say. It has not done any work for at least 15 years

Yes, the torques are measured just before movement.

Karsten

Yes...

Filled the differential with oil and gave it quite a bit of excersise, but the problem is still there

I don't much like my own theory but guess I will regret ignoring it.

When I initially unscrewed the grooved nut, it was very loose. I could take it off with almost no torque at all. It has probably been running like this for a while, which has probably worn down the taper roller bearings.

I think what is happening is the worn raceways cutting through the oil film upon standstill (only takes about 5 seconds now)

I do feel a very slight cogging when turning the pinion, not much, but it is there. This should probably indicate a bearing problem?

Although I'm way beyond point of no return with this axle, it would probably be the right thing to abort restoring it further and begin to look for a better starting point From what I have heard, it is next to impossible to align the differential properly if it has been taken apart?

Any hints to a trustworthy source of a good rear axle, who would be willing to do an international shipment?

Brg,
Karsten

You may be correct ..
.. but , I have never seen a preload get attained with just 95 ft/lbs on the pin nut.
You may just have not seated the race yet , as it may have unseated/loosened from the inner flange running loose all that time

Usually, it take at leat 115 ft/lbs , and up to 150 ft/lbs , to attain 24/26 in/lbs bearing preload ...
your 130Nm is only about 95 ft/lbs, if I remember correctly [ just converting in my head]

,,,as you said it sat for a long time , it may even just be dirt............

Well, at this point I guess it cant hurt to tighten it up a little further, worth a try at least.

If I shall excercise it further I'll have to find an automated way to do so, only machine I have which is up to the task is my battery DeWALT in low gear, all the others runs hot very quickly

Brg,
Karsten

..as you creep up on tightening the pin nut . give your tool a few taps in between tightenings so you know the bearing races are seating in the casing flanges, if you know what I mean...this will assure seating without further crushing the sleeve demensions..

Well, I tightend the grooved nut up to specs, but the problem is still there...

I'm quite sure the taper roller bearings are dead. I will try to change these. Unfortunately I can't find my book with the differential crownwheel and pinion alignment data, but I do have some generic information to work from. Basically I just want to check that it looks right before assembly.

Brg,

Karsten

You will have to take it apart .
Remember , it is the spacers in the rear of the pinion and the the ones in the left axle casing that determine the ring/pinion mesh, not the crush sleeve.. The crush sleeve only determines bearing preload .. If you change the pinion bearings, the preload on new bearing W/O ring gear is 15 in/lb, or 5-10 for old bearings. This is just pinion shaft. The other 25 in/lbs I gave you is total drag for assembled differential.

I have some info , if you need it. PM me.....

Arthur,

Thanks a lot, you are most helpful.

Would it be a good idea to preload the bearing before the crownwheel is attached? Of course after the correct mesh is determined.
Would you recommend using grease to visualize the mesh of should I use something else?

I'll PM you for the info.

Brg,
Karsten

The advantage to setting crush w/o ring gear is you know for sure what the load of that set of pinion bearings is.. with total diff load , you are not sure where the load is coming from..
I will send you the info.

I finally got the pinion bearings and took the differential apart today.

Somehow rust had developed at the innerside of the inner ring of the front pinion bearing, also a rusty substance was to be found inside the crush sleeve. This is probably why I got these strange stick and slip readings.

The pinion bearings were worn, but not as much as I expected. No pitting on the bearing race ways but some tiny grooves all the way around the race ways.

However the one differential bearing is in bad shape having a large pit on the outher bearing race way. I'm glad to discover this at this point.

The "new" rear axle I bought in Germany should arrive any day, I will probably take the decision about further actions upon evaluating this axle.

Brg,
Karsten