Sudden loss of drive. Gearbox/Transfer box?

Evening all.

Whilst I was driving home earlier tonight, I was going about 50mph in 5th gear, when all of a sudden the revs increased. I then took my foot off the accelerator then placed it back on a second or so after, the engine rev'd up but with no forward drive It was just coasting.

I rolled to a stop on the side of the road. Placed it into first gear with the engine on hand break off and released the clutch there was no forward movement just a grinding noise. I tried this in second also, went through this process in high and low range and high and low range diff lock. All of came with the same result no drive and just a fair bit of grinding.

So with pot luck a member from here Farra was driving past very kindly stopped and towed me 4 miles home. raise:

The question is I have no idea what is wrong, I was hoping someone else may be able to shed some light???

Its a 1988 90 with a 200tdi discovery engine, Lt77 gear box and the transfer box is 1.4 ratio. It has also had a new clutch fitted about 6-7K miles ago.

Thanks in advance.

if youve lost all drive and diff lock doesnt make any difference ,check a prop doesnt spin whilst its in gear as it may not be actually locking the diff ,check top see if gear noise changes when changing gears,check mainshaft splines by removing pto cover

Thanks jamesmartin I will check evening you have mentioned tomorrow in day light, will post results.

I have been to have a look,

1st attempt gear box and low box both in neutral with one wheel off the ground (rear near side) diff and prop span freely.

2nd attempt after turing the engine on and releasing the clutch in gear to see what would happen. Then try the same thing with the same wheel off the ground the diffs and prop will not turn.

Im now going out to take the pto cover off.

jamesmartin said:

check mainshaft splines by removing pto cover

Click to expand...

What am I actually checking for here, as Im not to sure what to look for. :behindsofa:

input gear is splined to rear of mainshaft if splines have gone main shaft will spin inside input gear ,you will see it if you try it in gear with engine running

yeah my money is on the drive splines on the gearbox, its the right age for the non-good oil starved splines to be present.

:-(

I had something very similar a while back. Turned out to be the center of the clutch ripped out.

thegavs said:

I had something very similar a while back. Turned out to be the center of the clutch ripped out.

Click to expand...

the clutch has only done 6-7k so i hope it is not that.

forgot to also mention that there has been a fair bit of a loud clonking noise recently when changing gear and coming off the clutch a little too quick.

Rawly86 said:

forgot to also mention that there has been a fair bit of a loud clonking noise recently when changing gear and coming off the clutch a little too quick.

Click to expand...

I had exactly the same symptoms. Clonking when reversing and setting off forward. I was reversing into my parking space outside the flat, Big Bang and no drive, just a jangley bag of spanners noise in hi/lo and diff lock. After taking gearbox and tfer box apart, it was the splines on the female part of the transfer box. Totally sheared off inside. The gearbox mainshaft was fine. My money is on this. Remedied with replacement disco transfer box.

Ed

I have a x drilled 1.4 input gear however they usually both wear and its goo dpractice to fit new gear when new gearbox is fitted

Right I bought a gearbox and transfer box off 200tdi-ayre. The plan was to fit it myself but time and a gravel driveway are not on my side so i'm taking it to a agricultural engineer (a client of my dads) .

The question is how long roughly should it take to fit with all the right tools and 4 post lift?

and if it all goes to plan, has anyone fitted one themselves?

Rawly86 said:

Right I bought a gearbox and transfer box off 200tdi-ayre. The plan was to fit it myself but time and a gravel driveway are not on my side so i'm taking it to a agricultural engineer (a client of my dads) .

The question is how long roughly should it take to fit with all the right tools and 4 post lift?

and if it all goes to plan, has anyone fitted one themselves?

Click to expand...

2 hours

top-cat said:

2 hours

Click to expand...

Thank you, thats not long as I thought.