gearbox problem?
 

Hi,

I just bought a '95 V8 Discovery. The engine runs like a clock.
I can't get the Disco to move. Shifting gears and moving between Lo and Hi feels like positive shifts but no power gets transferred from the engine to the gearbox.

The the transfer box and the gearbox engage on the driveshaft. I tested this by pushing the disco backwards and forwards and selecting the gears. With the transfer box and the gearbox in neutral the Disco runs free. With just one the transfer box or the gearbox shifted into gear it still runs free. Then I select Hi or Lo and any gear on the gearbox I get the resistance from the gearbox and transfer box on the wheels.

With the Disco engine running and the gears selected there is no noise. I would expect to hear noise if something is broken?

Any ideas or anyone ever experienced this?

have you checked the fluid?

moved to the correct forum.

Check fluid in transfer case, its all gears if ran low on fluid it could be locked up

This may be a silly question but are you talking 5 speed or automatic here?

Oil level good. It's a manual gearbox

hows the clutch feel?

This may be a silly question but are you talking 5 speed or automatic here?

not at all a rather important question, i should have asked it myself.

Let me see if I understand this correctly:

If you have the vehicle off, tranny in 1st (or any) gear ...and the xfer in low or high and rock the vehicle back/fourth, does it stop the movement, like it's in gear? Or, does it feel like it's always in neutral? What happens when you lock the center diff (xfer case?).

If you can't move the vehicle while in gear but it rolls free while either unit is in N, then I'd look at the clutch assembly because that would lead one to think the clutch is not sitting on the flywheel, which is odd. I've seen other vehicles where the ball stud (or whatever the clutch fork rides on) wears through the fork ... but if this were the case, then the clutch would be engaged all the time so it should lurch if you tried to start it in gear. Then that would lead one to believe there was another problem with the clutch or throw-out bearing. Is there an inspection cover at the bottom of the bell housing you can remove and peer up into?

Another thing I've seen on other 4x4's is that the bottom of the transmission shifter ball wears and either the side pins (or the keyway's) wear from years of use and no grease, and/or, the ball on the end wears to the point where it won't properly shift even though you think it is. On older Toyota transmissions, there was a plastic cap that fit over the ball at the bottom tip of the shifter and it would eventually get brittle and crack and fall off. Then ya couldn't get it into gear. In cases like this, I've built up the worn areas with weld, then re-grind or machine back to how it should be ...and replace any plastic sliders or caps.

Another thing to consider is that most manual transmission shifting or gear selecting mechanisms consist of a top assembly that contains sliding rails and forks. Basically the 'shifting' hardware. The forks are attached to the rails (rods basically with a couple detents in them). As one moves the shifting lever forward or back, it slides the rails, which in turn moves the FORKS back and fourth. The forks themselves are U-shaped and fit around an internally-toothed collar inside your transmission which when slid forward, locks onto a gear ...essentially engages a gear. The forks are typically pinned to the rail with a hollow pin, and I've seen more than once where such a pin wears over time and eventually falls out. When that happens, the rail can slide back/fourth all it wants as you put in into gear but the fork goes nowhere. It can have all the 'feel' like it's going into gear but doesn't engage the gear. This means that it would (or could) be stuck in Neutral. It's all slippery inside with grease and lube and you'd never know if the fork weren't moving. There wouldn't be any friction. I put a tranny together once and forgot to drive in the pin and had this happen. Fortunately I did a pre-install check caught it before installing it. On a side note (for the betterment of others), I've also seen where such a pin wears and 'works' it's way partially out and then internally binds causing the feeling of not being able to shift out of gear.

If all this seems to make sense and is what you seem to be experiencing, you could check it out by removing the console (10 min job) and see if you can get the shifter lever out and peer into the transmission. Again, I haven't worked on Land Rover Manual transmissions (but most makes are about the same), and generally there is a small retainer plate that holds in the shifter. If you removed that, you could probably get a look with a flashlight and manually move the rails and see if you can 'see' any movement inside the transmission. The rails aren't always below the shifter so you might not see anything. However, most transmissions have a separate shifting assembly that holds the rails and forks and bolts to the top of the tranny ...and you can generally remove this unit if the tranny is out of the vehicle (w/o having to disassemble the whole transmission) and if the fork pin had fallen out of place, you could replace it rather easily.

And if this were all the case and your rig has a bunch of miles on it, this would be the time to consider pulling the tranny apart to at least install new synchros and maybe a countershaft front bearing (since you're right there and manuals are easy to work on) and also install a new engine rear main oil seal (because they ALWAYS leak) and to replace it would mean pulling the tranny anyway.

This is all conjecture and I've worked on a good number of manual transmissions, but not land rovers ....just throwing out some ideas.

If this doesn't sound like it's it, Give us a few more hints or clues.. Keep us up to speed.

Good luck.

The clutch is easy to push down. i'll need to bleed the clutch but the clutch will release when pushed down. now it feels like its not taking on the flywheel.