Rear diff on 88 RRC knocking

I'm not sure exactly what he means by pinion gear carrier TBH.

There are a few items that can wear and cause slop in a diff but if it's the pinion bearings that have gone then they can be replaced quite easily. To test them take the tension of the propshaft (chock the wheels and take the handbrake off, gearbox in neutral) you should then be able to rotate the propshaft slightly. See if there is any up and down movement in the diff where the propshaft meets it. If there is then either the pinion bearings need replacing or the drive flange is worn.

If there is movement then take the propshaft off at the diff end and try moving the drive flange up and down whilst keeping an eye on the nut and shaft in the middle. If the drive flange is worn then you will get movement in the flange but the nut and shaft will stay put - the drive flange can be replaced with the diff in situ and is often misdiagnosed as a worn pinion bearing. (I have to confess that I once removed a front diff to replace the pinion bearings only to realise when I had the diff on the bench that it was the drive flange - spending two hours to do a

Internally, the cross shaft that the planetary gears run on can wear an oval hole in the carrier which requires a new carrier but you'd have to have removed the diff to be sure of that diagnosis. A knocking or clicking noise could be anything but normally I'd expect more of a rumble

Removing a rear diff is a simple enough job. You may have to remove both wheels though in which case you'll need axle stands. Don;t forget to chock the wheels - your parking brake won't stop the vehicle moving once you remove the halfshafts ! Some wheels allow you to remove the half shafts without removing the wheels but most Range Rover wheels don't. If you don't have axle stands or feel safer with the wheels on the ground then remove a wheel, remove the halfshaft and put the wheel back on then do the same the other side. The manual will have a description for removing the half shafts but in essence you undo the 5 bolts that hold the drive flange to the hub and the drive flange, complete with half shaft, pulls out of the axle. Pull both half shafts out about 6 inches ( or all the way if you have room), disconnect the propshaft (if you only disconnect the diff end then tie the prop up SECURELY out of the way), drain the oil from the diff pan (drain plug under the axle), undo the ring of bolts holding the diff to the axle casing and pull the diff out. If you've not lifted a diff berore then be aware they are heavy. I usually lie on my back under the diff and lower it onto my chest then roll it onto the ground.

cheers

Dave W.

Thanks Dave,

There is no play in the UJ or the i/p shaft to the diff. With the RR supported on the lift with all wheels off the ground we were able to get some monumental knocks from the diff - even louder with the oil filler plug removed. Seems pretty conclusive that there is something amiss with the guts of the diff. In fact it got even worse as I drove gingerly home.

It seems that Paddock have recon units with 6 months warranty for ~ £100. Any views?

I was also wondering if I should remove the rear propshaft for my return journey to my spanner wielder and drive it to him with the diff locked?

On the other hand I do have four big axle stands and a couple of hydraulic jacks. The genuine manual says nothing about removing drive shafts, let alone removing the diff - it assumes that you only want to overhaul the diff. But from a closer look at the spares book what you say about pulling the drive shafts out makes more sense to me. Is it really that simple? Just pull the shafts, disconnect the prop, unbolt the diff and discard, refit the new diff with a new gasket (joint washer?) and refit the shafts. No awkward setting up of backlash and clearances? What about getting the drive shafts back into the differential?

Thanks Richard

In message , Dave White writes

Then what do you do with the ep90 that drains down your arm and works it's way around the neck of your overalls ... :-)

Treat it as free a waterproofing or, if you wear them for welding, or as an accelerant?

Richard ;-)

and smells like cat wee

I usually take it as a given that crawling under a Land Rover is always going to lead to ep90 supplying a "natural" Land Rover water resistance and insulation to your overalls :-)

cheers

Dave W.

Doesn't sound like too bad a price, second hand units seem to go for around 40 to 50 quid normally but if these have been reconditioned properly, which I would guess should include renewing and reshimming the pinion bearings and replacing the carrier bearings then that doesn't sound too bad.

As long as you have the drive shafts in place the diff is still going to be turning so removing the prop shaft probably wouldn't make any difference. If you were to replace the rear drive shafts with two spare front ones (they are about 8 inches long) then it would be worth doing. I carry two front drive shafts in my competition motor for that very purpose.

Yes, it is that simple... normally. Sometimes you get small burrs on the end of the drive shafts that can make it difficult to get them to slide out but most of the time they pull out without any real effort. You only need to set up the backlash etc.. when you take the diff itself apart - with a recon unit it will already be set up.

Getting the drive shafts back in isn't too bad, you just slide it in until it stops, pull it back slightly, manipulate the drive flange to lift the far end of the drive shaft and rotate it until it engages then push it home. It's easier to do than it is to explain it !

You'll need gaskets and sealant for the diff and the two drive flanges.

If you go for the recon one you can always rebuild the old one at your leisure. They really aren't difficult to set up, all this talk of back lash and the "there be dragons here" when it comes to diffs is a bit overkill. Once you actually get the thing on the bench you'll find it's pretty obvious how they go together.

cheers

Dave W.

Well, you've convinced me! I'm looking forward to the easier-to-do-than-explain drive shaft fitting tho'. When I replaced the propshaft on my bike (1150GS Beemer) it was an absolute nightmare of wiggling with screwdrivers to get the bloody splines lined up at the gearbox end. Still, at least I won't have a pair of uncooperative UJs to make life interesting.

Cheers

Richard

differential?

Richard,

Don't worry I'm not ignoring you!. I tried to reply to your e mail you sent re Holey chassis and it got bounced back twice. Chassis is still holey and the MOT looms ever nearer.........

Dom J