Is My Diff Broken

[Cannon]

Hi All,

I was driving home yesterday & next thing I here a few clicks, a crunch & the a high pitched whine.

I limped home (about 2kms thankfully) with all sorts of terrible expensive noises emitting from the car.

This afternoon I jacked up the rear put everything in neutral with the handbrake off & rotated a rear wheel.

Sometimes the opposite wheel would spin, sometimes not.

The drive shaft also only spun sometimes.

The wheels would still spin with everything in gear & handbrake on.


Is my Diff Broken - YouTube (http://youtu.be/nk2AWeyJKac)



So, is it time for an Ashcroft ATB?

[Homestar]

Could be just an axle.?

[Blknight.aus]

most likely the axle unless the center pin has gone which is unlikely as it hasnt thrown metal out the front of the housing yet.

[Slunnie]

I can assure you it won't be a half shaft, if its a half shaft you won't get any movement of the wheels across the axle like that. I would be thinking that on the D2 axle it is the hemisphere, and of that part it will more than likely be the planetary gears. That said, if you've broken the planetary gears I would also bet that if you have standard half shafts that they will also be twisted and need replacing.

[walker]

Agree. And with the noises you are describing it is suggesting Spider gears. They are the weakest point in the D2 drivetrain.

[wrinklearthur]

Drop that diff out and clean the inside of the housing, wash it out with kero and then by using a powerful magnet gather any of the minute metal particles left from the disintegrating parts.

Using your peepers, check out the diff centre for any trophies for the den wall and find your self another diff.

I would now grab another diff centre from a low K wreck and have a Tru Trac fitted, making the most out of that time the bus is off the road.

I am reasonably sure that the rear diffs for the D2 are the same as the D1's, 1994 onwards, from the time when they went to fine spline axles and started using the rubber uni joint.
.

[disco 3 door]

most likely the axle unless the center pin has gone which is unlikely as it hasnt thrown metal out the front of the housing yet.
As Arthur stated if D1 & D2 diffs are the same, it is a good posibility (from personal expeirence )is a broken cross shaft. I did not do any other damage. Mine broke on take off.

[Slunnie]

D1 and D2 diffs are not exactly the same. The hemisphere has been changed so the cross pins are mounted differently and in a way that reduces the stress in them, which is why D2s tend to not break the cross pin like other rover type diffs, but do tear apart he planetary (spider) gears instead.

I'd just have an alternate aftermarket hemisphere fitted also such as a locker or ATB. They're probably all stronger than standard.

[wrinklearthur]

D1 and D2 diffs are not exactly the same. The hemisphere has been changed so the cross pins are mounted differently -----

I will have a look at the two rear diff centres I have in my workshop tomorrow,there is one each from a D1 and D2.

If you remove the cage and fit a locking centre it shouldn't matter then whether it's from a D1 or D2 ?
.

[Cannon]

Thanks for the replies.

It looks as though the noises are actually coming from the transfer case. :-(

Interesting that the diff may be broken as well.

[wrinklearthur]

This afternoon I jacked up the rear put everything in neutral with the handbrake off & rotated a rear wheel.

Sometimes the opposite wheel would spin, sometimes not.
The drive shaft also only spun sometimes.

I read this again and yes that is right, if the tail shaft, the opposite and closest wheel are unrestrained, one or another will spin, either both together or individually, when turning any one of the wheels or the tailshaft .


The wheels would still spin with everything in gear & handbrake on.

With the handbrake on and the other side wheel firmly on the ground, try and turn the raised wheel and if the diff is ok, it should only move about 5° in either direction until the back lash is taken up and then move no more.

If the diff centre is broken completely, doing that same test the wheel will keep rotating.

Sorry, I should have read your original post a bit more carefully. :(

Do that test for the diff again and then you can confirm one way or the other the condition of the rear diff, before we start diagnosing the transfer box.
.

[Cannon]

Replacement transfer case is in.

I never realised how noisy the old one was:o

It's now like riding in a silent bubble with just the V8 note in the background.

Diff is OK.