Advice re Torquing rear hub nut

[WGB]

A question for Styria or someone else with the clevers.

I have never torqued up a rear hub and realise the forces involved to crush the crush washer and get the correct 0.04mm freeplay are quite large.

I propose bolting the hub to one of the old discs in the reverse direction to normal and welding some angle iron to the back of the disc so that it can be gripped in a vice and protect the hub from deformation.

I would appreciate either advice or personal experiences or both before I buggar it up and need to start again.

Bill

 

[Styria]

Hi Bill, regarding tightening torque for adjustment of rear wheel bearing. The workshop manual provides no specifications other than:

1. Attach dial gauge holder.
2.Set end play (0.04 - 0.06 mm) of rear axle shaft flange by tightening the slot nut. Keep turning rear axle shaft flange several times and check end play at several points.

3. CAUTION ! When excessive tightening of slot nut has left no more end play, do not make corrections by loosening the slot nut, but be sure to remove the excessively preloaded spacing sleeve in each case and install NEW SPACING SLEEVE.

4. Lock slot nut by bending into pertinent grooves in rear axle shaft flange at two points.

The recommended dial gauge run-out measurement (say 0.04 mm) obviates the need to specify a torque figure for that slotted nut that you have the special adaptor for.

I have done this job about four years ago in preparation for installing a completely new rear suspension and driveline, including a 2.43:1 differential from a Ch. 126 - 500, but this job is still to be done. Getting back to that crushable spacing sleeve, I would suggest that you could consider using the old one as long as the correct run-out can be obtained. It'd make life a lot easier. Regards Styria

 

[WGB]

Thanks for the reply Styria.

I am just about to go down to the shed and torque it up.

The old hub was fine and RonB on the M-100 site suggested using the old crushwasher as well so I am going to Mike both of them and measure the relative depth of the two and then decide.

Sclass also suggested that I should use a more stable method of holding the hub if the torque levels end up high to prevent distortion of the hub so I have welded a piece of square section steel to the back of the old brake disc so it can be held in the vice with the hub bolted to it on the reverse side to where it is normally bolted.

I will post pictures later on.

Bill

 

[WGB]

Progress report.

Pressed out the hub again and swapped the new crush washer for the old before I had torqued anything up.

New crush washer measured 12.15mm
Old crush washer measured 11.45 mm.

Hub torqued up easily with the old crush washer with a little tightness near the end and at the moment it measures 0.05mm end float on the dial gauge. Don't know if I'm game to go the last 0.01mm.

I've left it unpeened and will see in the morning.

Pictures to follow when arm finished and all painted.

Bill

 

[Styria]

Sounds pretty good to me, Bill. As a natter of interest, are you going to have any work done on the diff ? Does it have a slight whine as is not all that unusual for a 6.9 diff. Just as a matter of interest, I have come across one diff where one of the bolts let go and destroyed crown wheel and pinion.

I am almost inclined to check the crown wheel/pinion bolts as part of a major service. I've also come across this 'loose bolts' situation on a 6.3 as well as 3.5 diff. Anyway, it's up to you, but right now it is easy to get at the various parts. Regards Styria

 

[WGB]

I will take your advice and check the crown wheel bolts as I am still waiting for new correct thickness thrust washers for the flanges.

They were supposed to be coming from Germany and taking 3weeks - 2 1/2 weeks ago so I only have the backplate loosely on with a couple of bolts to keep the dirt out.

My diff could never be described as silent but it wasn't too bad and I hope the process of changing the pinion seal hasn't unsettled anything.

Bill