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MacMan
3rd August 2005, 08:21 AM
Over the weekend I did the last of the major service fluid changes - the axles. The front axle was easy enough, but the swivel housings were a bit of a fiddle. The last person to service the axles did up all the tapered threads with gasket goo, which necessitated me working under the vehicle with a 2' breaker bar to extract the fillers and drain points, and to my amazement the swivel fillers too! I thought the whole idea with tapered threads was that they self seal to a degree, but the use of gasket goo on ALL of the threads was just silly. The passenger side swivel filler plug was completely distorted from a previous extraction in a way that only hundreds of foot pounds of force can do, but still they used goo. Sure if a car has a leaking problem, then careful application of goo to the last two or three threads seals it without sticking the plugs so hard that 90kg hanging off a standard ratchet handle does nothing.

The oil that came out smelled a little rank, and showed signs of dispersed moisture, but much to my satisfaction there was very little in the way of swarf or hard facing chips. All oil was replaced with Penrite Hypoid Gear Oil 80W-90 through a little "Tom Thumb" oil pump from Autobarn. (This little oil pump is the ***** for doing all oil insertion jobs on diffs and tranies and MUCH better than the 100cc syringe I used to use. A bargain at $24.) The result is a slightly quieter driveline so all I really have now is a little bit of transfer whine at 100kph and V8 music. The rear diff oil was in surprisingly good condition, and just for curiosity's sake I pulled one of the half shafts to find out whether I am running 10 or 24 spline. To my relief I found a very healthy looking 24 spline shaft with no serious fretting. There was a little it of flaring of the edges, but the splines are obviously engaged very well and along their full length in the ARB locker. See pics below.

http://www.aulro.com/albums/Disco-rear-half-shafts-July-05/Spline_1.jpg

http://www.aulro.com/albums/Disco-rear-half-shafts-July-05/Spline_2.jpg

The oil in the bearings was a little on the grotty side, with quite a rusty tinge to it. I suspect the main source of discolouration comes from the inside of the shaft cap that bolts to the hub, as this had a fair accumulation of gunge. I cleaned what I could out, and checked the bearings for play but all was peachy.

http://www.aulro.com/albums/Disco-rear-half-shafts-July-05/Hub_1.jpg

http://www.aulro.com/albums/Disco-rear-half-shafts-July-05/Hub_2.jpg

I reinserted the shaft and sealed the end cap/hub union with RTV silicon rather than a gasket - it seems that is the convention these days, and none of the hubs on the car have gaskets now. Just to be sure the bearings got a good drink I jacked up the opposite side as far as the garage roof would allow once the axle was filled and left it to sit for an hour. As a matter of course I will pull the other shaft out and inspect it. I think I am just looking for an excuse to step up to Maxidrives!

MacMan
3rd August 2005, 08:25 AM
By the way, nothing is leaking without reassembly with gasket goo. We'll see how long that keeps up and whether any water is let in next time the thing gets stuck in some water.

LRHybrid100
3rd August 2005, 09:18 AM
may I suggest one of these fluid transfer pumps - good for gearboxes / transfers / axels as it can hold 1 litre at a time and pull EP90 out of a 5 litre tank very easily.

http://www.difflock.com/wm10D_02606/ws20img/ws20img_5001/inventory/DF2.jpg

This is one I bought from Difflock in the UK, but have seen similar for about $40 at my local engineering supplies.

HTH

LRH

mauricem
3rd August 2005, 09:30 AM
Interesting stuff, was wondering about the 10 vs 24 spline shafts. You indicated your disco could have had either type.What year is your disco?(couldnt see it on your profile) A quick search indicated that the 10 spline was only used up till 92. Do you know if thats right or did LR just use whatever was available at the time!

MacMan
3rd August 2005, 09:48 AM
Ours is a late '93 - one of the first with the 3.9i motor. They still have the LT77 and the old style interior, but they had updated the axles by then. I wanted to see for myself since I had read conflicting stories about when the splines changed. It was the one way to be sure!

The nice thing about the Tom Thumb pump is that it will fit a 2.5L oil container so you can pump straight out of the bottle. It does take a few dozen strokes to fill the diff, but you have heaps of control.