Hi all,
i am in the process of changing my clutch. Upon the removal of the transfer box from gearbox, i noticed some small metallic flakes in front of the main shaft bearing. They are copper colored.
just wondering if anyone has an idea what it might be from?
i am hoping it's something as simple as a bearing. i thought I'd ask
for feedback before i open it up.
i took a few photos below.
That is the remains of the centre diff copper washers from the planetary gears. They will need replacing and it is well worth putting a rebuild kit through at about 200 for the kit. Depending on age and use the rest of the box can be fine and you can get away with just the washers being replaced for a few dollars and your time. But sensible to do the lot.
if you're spenting $200 then consider spending some more and get the Ashcroft (or other make) of torque biase unit - check out why rover centre diffs can fail. Phone them, give credit card details and address, cheap airfreight (compared to within Oz), at your door in about a week or less. If not, then consider a solid cross pin instead of the two piece set up.
just been looking Rave and can see in the differential components there are 4 Dished thrust washers and 2 selective thrust washers are these the ones you mean?
Is this something you would do yourself...i've replaced a head and number of other stuff, i have a little bit of mechanical nous.
The 4 dished thrust washes are the ones that have failed. I am not replacing the selective washes as i have a second transfer case in pieces and i can select the best out of the two. Unfortunately the centre diff is a poor design and this is where the diff lock needs to be used where there is a chance of significant wheel spin occurring. It wouldn't take much wheel spin, before traction control works, to wear and burnout those thrust washes!
The differential is a precision component and technically needs to be correctly set up. However, it is not something that you and i can do in our workshop and considering there maybe wear internally internally, i can only suggest by replacing the thrust washes now would only improve on the current situation.
Likewise with the transfer case and gearbox, it is a precision component and to correctly overhaul replacing bearings etc, you need to have correct shims 2 set specified preload on the bearings. Once again i have a second transfer case in pieces and i'm currently selecting the most suitable shims to get close to the correct preload.
I wonder how other people go just replacing bearings?
Good luck!
Incidently the thrust washer part number it is FRC-6968
is it right to assume that the destroyed thrust washers will be dispersed throughout the transfer box.
if so do i need to have the whole thing stripped down, cleaned and re-assembled?
anyone had a similar situation and associated fix?
Sounds like you have sufficient experience. The centre diff housing with diff centre can be removed without removing the rest of the transfer case - case bolts and linkages - although it sounds like you have the whole lot out already. I'm probably a little less sensitive to set up than Disco 2 Driver, where in the past I just crack open the diff, clean it out, put in new washers and lock-tite it closed, reinstall. Getting metal fragments out of the rest of the case would be advisable but I think not essential - use the inspection hole and probe around with you fingers or suction device, or flush. Follow the manuals instructions if in doubt. I'm going to replace any future centre with a torque biasing unit, as previously stated. I have four Disco's and its been interesting to see the degree of wear - 200,000k, modest wear, 400,000 significant wear, 600,000 three are cigarette paper thin and the fourth gone entirely. All centres were thickly coated with sediment, around the washers, indicating poor lubrication to the area. One of the more tech savvy has a thread on how to improve flow into the diff centre, just can't remember who - Bush65, Blknight??
In my situation after pulling it apart and seeing the condition of the inside i could have just replaced the washers and no doubt the transfer case would have gone a long time before further attention.
If you decided to just replace washers, for the sake of a couple of litres of oil, I'd just give it a flush.
Last edited by Disco Driver; 15th March 2014 at 05:06 PM.
Reason: update
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