Thread: LT95 Centre Diff Befuddlement

Originally Posted by Davo

I must ring my parts guys about this, but anyway . . .

I have a few LT95s that I've stripped and now I have a lovely big pile of parts. This includes a late centre diff, and the 90/110 manual helpfully points out the upgrades that include bushes for the side gears, modified cross pins, an oil retaining ring, and so on.

It then unhelpfully does not explain how to set up this later diff. There are the instructions for the older diff but this newer one has a range of thrust washers for the side gears to control the endfloat.

Then you look at the LT230R, which has side gear endfloat measured with feeler gauges through slots in the side of the diff housing. Then, there's the LT230T, where you put an output shaft and handbrake drum on and measure the force required to turn it with a spring balance.

But you can't do that with this diff. So the only thing I can think of is to assemble the diff and then use a dial gauge with a big extension on it to measure the endfloat, levering the side gears back and forth. Yes? No?

The other thing is the side bushes don't appear to have a part number. Though they are replaceable. Any ideas?

I think someone was sleeping when they wrote this bit of the manual.

The thrust washers are a standard thickness. part number FRC6968 and the bushes in the diff halves are replaceable but unavailable from LR - you have to buy the complete diff assy to get them. However you can buy a bush material from SKF and machine it to fit if you need to replace them. I havent had to replace mine as yet as it is usually the thrust washers that go first and you WILL know it when they do.The dimensions of the oe bush are 40 X44 X13. the SKF glycodur bush is 40 X 44 X 20. Just machine 7mm off the width and hey presto.There is a thrust washer under the side gears that is available in 5 thicknesses for 1.05mm to 1.45mm in .10 increments. This is where you adjust backlash/endfloat. Only way to do it is assemble and check with 2 dummy shafts until you get it right.........Bearman

Ta very much for that. Yes, it's the side gears thrusts I was wondering about. What do you mean by using two dummy shafts? Do you just adjust until you don't have any gear play or is it an endfloat measurement or a torque measurement?

Yes, the side gear bushes don't look too bad . . . you know how it is . . . you'd just rather not replace them if you can get out of it, but feel like you should. (I wonder how much use they actually see.) Thanks for the tip about the SKF bushes. I really do need a lathe. But seeing how I'm way out in the bush maybe a hacksaw would do it!

What I do is adjust until the gears are firm but not tight or jumpy. Use old front and rear shafts to check backlash. Or use your current shafts. Make sure there is not excessive wear on the shaft splines where they engage the CD side gears. This will give you play if it is excessive. The correct figure for adjustment is 0.025mm endfloat on the side gears. But it is nigh impossible to check this with feeler gauges. Also dont forget to use Loctite 241 on the bolts that hold the 2 halves together and torque to 40-50 ft/lb. This is important as it is a common problem for the bolts to work loose. Regards......Bearman