Defender Lt77 gearbox-knackered?

Hey,

Possible big problem with gearbox on my defender 200tdi, any help or advice would be greatly appreciated.

Bought landy 2 years ago, guy selling landy said gearbox was making a whining noise and was knackered.
Checked gearbox, no oil hence whining noise (i foolishly assumed!)
Changed filters and oil seals, put in high grade ep90 oil i obtained from a tribologist friend of mine.
All seemed fine apart from difficulty getting second gear when oil in gearbox was cold, decided i could live with that as the whining had stopped.
Now , a little over 18 months later the whining is back but this time when in first or second gear there is also a squealing sound coming from somewhere underneath the middle front seat, doesnt happen in neutral but does seem to happen in 3rd, 4th and 5th but intermittently.
Could this be a simple probelm or a big one?
I know its hard to give advice with such poor info but any theories would be a great help for fault finding.
Thanks

Sounds like its new gearbox time.

EP90 should never be used in the gearbox! It takes ATF or MTF - someone else can elaborate on those two. EP90 is too thick, only for transfer box and diffs.

Noises could be bearings, they usually whine if on the way out.

Haha, ok i think ive killed my gearbox by putting the wrong oil in. Bugger.

Yeah good point on the oil. EP90 goes in the transfer and poss axles (cant remember that one) and def atf in gearbox....OOPS

As mentioned, you want ATF in an LT77. You should also be changing the oil every two years... so, depending on the milage you've done in those 18 months the oil will be due a change. Particularly as it's completely the wrong type of fluid...

change the fluid you might be lucky...

EP90 makes the gears 'stiff' to use, if you have the whining back it's usually bearings...

Get some prices...

1. Rebuilt gearbox
2. Exchange box
3. Strip and re-build on your box

See what you think, get a specialist to look at yours, it might(?) not be dead.

Ok, dropped oil from transfer box, flushed it and changed it. no signs of metal chunks in the sump. Did the same with gearbox, put in correct oil after flushing it out, again no signs of any metal.
Removed middle seat and steel plate to expose transfer box and rear prop and went for a drive, whining gone, squealing still there.
Was wondering if knackered UJs on prop could be causing squealing?
Im going to remove the rear prop and go for a spin, if the squealing continues then i think you're right and its out with the gearbox and to a specialist for a diagnosis.
Thanks for the advice and the info on gearbox oil. Much appreciated

dodgyrob said:

Ok, dropped oil from transfer box, flushed it and changed it. no signs of metal chunks in the sump. Did the same with gearbox, put in correct oil after flushing it out, again no signs of any metal.
Removed middle seat and steel plate to expose transfer box and rear prop and went for a drive, whining gone, squealing still there.
Was wondering if knackered UJs on prop could be causing squealing?
Im going to remove the rear prop and go for a spin, if the squealing continues then i think you're right and its out with the gearbox and to a specialist for a diagnosis.
Thanks for the advice and the info on gearbox oil. Much appreciated

Click to expand...

Yep - squealing can definitely be caused by dodgy UJs, one I replaced recently was causing a terrible squealing noise under acceleration and deceleration. Get under her and give the props a good shake to see if there is any play in the UJs.

If not, try greasing them (if they have grease nipples fitted, some don't). As a last resort you could try spraying them with some spray lubricant to see if it temporarily quietens the noise, if it does then you know that's your problem

dodgyrob said:

Ok, dropped oil from transfer box, flushed it and changed it. no signs of metal chunks in the sump. Did the same with gearbox, put in correct oil after flushing it out, again no signs of any metal.
Removed middle seat and steel plate to expose transfer box and rear prop and went for a drive, whining gone, squealing still there.
Was wondering if knackered UJs on prop could be causing squealing?
Im going to remove the rear prop and go for a spin, if the squealing continues then i think you're right and its out with the gearbox and to a specialist for a diagnosis.
Thanks for the advice and the info on gearbox oil. Much appreciated

Click to expand...

UJs, they're easy to re-build, I think Johnny did a fred for 'em, on 'ere somewheres.
should have grease nipples on 'em IIRC.

While your under the wagon, check the diff-oil levels, can be noisy anorl.

Ok, quick update for anyone whose interested....

Got under truck and had a look, rear UJ on rear prop completely shagged, removed prop shaft and went for a drive, No squealing at all. put prop back on squealing back. sprayed some machine lube on UJ squealing stopped so its definitely gonna need a new UJ on the rear prop shaft so thats my next task. I hope that will solve the problem......
Thanks again for the advice