XX-4WE Rear Diff Feels Like Grit

[Fiddybux]

Hi all,

I just rebuilt the rear diff of my XX4WE, no new parts, just gave evreything a good clean with motor spray and terps for the metal parts.

When rebuilt, the diff feels smooth enough until I set it down to run it and tighten the diff up so it's no longer slipping.

As soon as the diff is tight enough not to slip any more, then it feels really gritty.

If I back it off slightly, so that the diff slips a little, it feels a lot smoother - I suppose this makes sense as the diff parts aren't as tight so there is more give and it feels smoother. However, a slipping diff is completely unacceptable as I'm sure you'll all agree.

The car goes well enough though....just the diff feels nasty.

So what's going on here...do I need new carbide (?) balls, do I need a new diff gear? etc

I've heard that the diff ball bearing, both in the diff gear and the diff screw, can become squared off....is there a way to check this 'squaring-off' or is it invisible to the naked eye?

Thanks all.

[tyreman]

I would start by replacing the thrust bearing, as this can cause this sort of problem.

[Southwell]

I'd also change the diff rings as they can cause the problem too, i always change mine every couple of rebuilds and my diffs are pretty good even when the rest of the internals are old.

[Fiddybux]

Ok thanks for the tips lads...sorry for the daft question....I know what the diff rings are...but the thrust bearings...are these the ones inside the diff gear or the ones around the diff screw with the foam sealing ring / washers?

What about the squaring of the ball bearings I've heard about?

Cheers.

[Southwell]

The trust bearing is the one around the screw, these can round if the plates excessively wear, as well as the main balls, which is why i change mine frequently.

[Fiddybux]

OK gotcha (and still learning )...thanks...and fingers crossed.