Thread: Wheels wont move when diff is engaged

Originally Posted by AK83

Not being rude here .. just trying to get the correct terminology set straight!

CDL = centre diff lock
T/C = transfer case.

using the lever for CDL is locked or unlocked(not neutral). move the lever left(locked) or right(unlocked). On the road in daily use it should be to the right(unlocked). Move it to the left(locked) for off road situations.
using the lever for T/C (ie. gearing) is Hi(back) and Lo(forward) and in the middle position is Neutral.

So it seems that what you're saying is that if you lock the centre diff(ie. not put the Hi/Lo transfer case gearing in Neutral) you can't drive the vehicle(ie. as in off road) .. ie. it won't move?

So assuming that your use of the term Neutral = transfer case gearing(ie. not centre diff), if you put the lever in the centre position for Neutral, you can move the wheels by hand if jacked up?

I'm thinking, for example, that if your handbrake is stuck on(at the drum, not the handbrake lever, it will 'lock' the wheels to a degree.
With diff lock set to unlock, to the right(normal road use position), it really only locks the wheels on the rear axle only. If the CDL is set to locked, to the left(off road position), then the handbrake also locks the front axle too.

Even so, reason for all that is just to describe that the T/C and CDL can be a complicated system to test.

But going by your first post, I'd say you've suffered some destruction in the centre diff(CDL), causing it to jam up.
Many years ago when I had my RRC(LT95, ie. integrated transfer case and CDL) basically as you described. A 'CDL' diff shaft had broken into pieces causing it to lock solid internally. That is not lock up as in CDL locked for off road use .. lock up and RRC was rendered (almost undriveable!).

What I tried, back then, was to drive in reverse in low range... try not to turn at all where possible, it seemed to free up whatever inside the gearbox and I then drove home. Every time I had to make a sharp turn(as in Left or Right hander 90°) the car juddered badly with transmission wind up.
On curves it was OK tho. Drive home was about 10km but eventually got there.
I don't really remember any bang noise before the transfer/CDL got jammed, but on reversing it did 'let go' with a slight bang .. like a hammer hitting the gearbox.

I had it towed to my mechanic, stripped and found some diff cross shaft part in many pieces. I have no idea exactly what caused the lockup, but I guess that some loose piece had jammed up in a gear or something like that.

Hey mate, ive always kept it in high range, just before it happened the car did little jolts while driving so i parked up and let it sit for about half an hour, then when i came back to and started to drive off it did the same thing coming down the only exit ramp it comes to a complete stop and im unable to move at at all. So i rang up my girlfriends dad whos a mechanic and told him what happened, he suggest i put the CDL into neutral and jack up one of the wheels to release any tension built up in the wheels and thats as far as ive got to resolving the problem

MMM strange, do the TC leak in a Disco 1

Before I had mine rebuilt and resealed I had to top it up every 5,000 km with 200ml