No fourth in defender

[PAT303]

A mate of mine has just rung saying he has lost fourth gear,all the other gears work but not fourth.The box selects fourth but there is nothing there.It's a 96 with an R380.Any idea's. Pat

[sumo]

Might be wrong , but it could be a cracked selecter shaft, My deefer 130 did that one day with reverse,fiddled for a bit and got it, Aweek later luckily! in my driveway, could not get a gear. Turned out to be a broken selector shaft, evidentley they were alloy, and then went to steel.

Cheers Sumo.

[Blknight.aus]

what engines pushing it?

If its a diesel and anything like Brians box the input gear, shaft and front bearing will be knackerd allowing enough forward motion of the shaft to allow the engagement dogs to not engage.

If he can select 3rd and deselect 3rd then theres nothing wrong with the selectors.

Im still waiting on his permission to post up the stuff I found wrong with his box and LT85 that ate the front bearing but that will give you an idea.

[sumo]

Dave, not doubting what your saying, but where the gear stick sits in that little socket, held by that stupid grub screw is a area that can stuff, up, the grub screw actually does the damage if overtightened, on the alloy selector shaft, it cracks and then gets everything out of line, all gears one moment, then only some next,.Happened to me, and a guy in Newcastle NSW, fixed it stating it was a Treachous fault with landies fitted with that alloy shaft, because it could happen at any time!

Cheers Sumo.

[Blknight.aus]

yep, know about that, but when they start to go wrong (ie not selecting one gear) they will be a bit "differnt" in deselecting the gear above or below....

If you shift the box with the tcase in nuetral, the clutch in and the engine off you will hear things shifting, The stuffed selector makes an nasty cracking noise as everything pivots and the dodgy bearing route doesnt make any real difference, untill you do it with bits spinning.

[sumo]

OK! Ya convinced me!...lol.

Might bring my heap of chit up your way one day, Just to giive you a few more nightmares...lol

Cheers Sumo.

[Blknight.aus]

bring that stuff on, If its got a LR badge on it Im good for it...

my night mares start when working on busmasters having left gearbox panel up for inspection some idiot drops a secure item in there that promptly bounces up under the engine where its too large to get out the propshaft inspection ports in the hull and too heavy for the magnet grabs to shift.....


Damnit I just put that engine in..... :)

[sumo]

:D
bring that stuff on, If its got a LR badge on it Im good for it...

my night mares start when working on busmasters having left gearbox panel up for inspection some idiot drops a secure item in there that promptly bounces up under the engine where its too large to get out the propshaft inspection ports in the hull and too heavy for the magnet grabs to shift.....


Damnit I just put that engine in..... :)

:D:D:D:D:D:D:D:D:D

Cheers Sumo.

[ashtrans]

A mate of mine has just rung saying he has lost fourth gear,all the other gears work but not fourth.The box selects fourth but there is nothing there.It's a 96 with an R380.Any idea's. Pat

the pinion shaft is made in 2 parts then welded together, I would bet the weld has broke which means you can select 4th but get no drive as the dog teeth and not connected to the pinion anymore, all other gears are fine as they are driven off the layshaft,

[rick130]

the pinion shaft is made in 2 parts then welded together, I would bet the weld has broke which means you can select 4th but get no drive as the dog teeth and not connected to the pinion anymore, all other gears are fine as they are driven off the layshaft,


by the sound of things you've seen this happen once or twice before Dave ?

[ashtrans]

by the sound of things you've seen this happen once or twice before Dave ?

yes, couple of times on 4th but usually on 3rd or reverse,

[Blknight.aus]

I shoulda thought of that.... but I havent seen it in years...

Makes a lot more sense...

while its still drivable have him do a light deceleration in 3rd if the box growls at him its the bearing if it doesnt its shorn of engagement dogs....

you should be able to prove/disprove the selectors by pulling the gear shift out and runnin an endoscope or small mirror on a stick to eyeball the selectors and rods.

[rick130]

I shoulda thought of that.... but I havent seen it in years...

Makes a lot more sense...

<snip>

that's OK Dave, the other Dave's business is Land Rover transmissions, so if anyone's seen it, he would've ;)

[Freestyler]

Hi, From what I know about gearboxes ( I have the LT 85 out of my truck pulled apart on the benck needing a rebuilt ) if all the other gears are working I think that the teeth on the dog for 4th would be gone or on the baulk ring, any thing else and another gear wouldn't work. The teeth are on the pinion shaft. 4th gear is normally the gear you have least trouble with. Unless this is a know fault with the RT380 you are unlucky. Tim