300tdi manual will only move with diff lock on

I've owned my disco for about 4-5 weeks and slowly but surely things have been going wrong with it, only small things like the back door and passenger door not opening from the outside and the bonnet catch not working but these are jobs I can sort at my leisure as I don't use it that often.

Today however, I drove to Greggs for a pasty and thought to myself that it felt as though the gearbox/engine mounts were failing as there was quite a jolt when I either changed gear or dipped my clutch and when I got back in it there was no drive at all from any gear! When I put it in third, fourth and fifth there was a noise like something was spinning but loose or scratching against something! I tried going from high to low range but nothing happened. I then put the diff lock in and it drove! I'm no mechanic so I'm baffled as to why it would drive but even then there was a little clunk every time I changed gear.

It's now parked up in the workshop and I'm back to driving home in the van until I can get it sorted.

Any ideas what it could be?

Thanks

One Prop shaft dropped off, diff failure or maybe a front CV joint has let go.

Thanks for the quick reply, are either of these easy to spot? Not had time to get underneath today but I'm in the workshop all day tomorrow so will be getting on my back to check it out

Datatek said:

One Prop shaft dropped off, diff failure or maybe a front CV joint has let go.

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could also be a halfshaft snapped.

I'd googled about to try and find a simple explanation of how the system works - to save me ( or someone else ) typing it in... might be worth googling about so you understand the thing a bit better.

This happened to me a few weeks back. My problem was the centre pin in the rear diff. It had broken into three bits.

Robnixon said:

This happened to me a few weeks back. My problem was the centre pin in the rear diff. It had broken into three bits.

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Charming!!

Did you fix that diff, or fit another?

Another possibility is the drive gear has stripped.
Wheel off, rubber tit in the centre of the hub off and have a look!

Thanks for the posts guys, I will be getting on my back this evening to check it out. Im not a complete numpty when it comes to mechanics but having never had a 4x4 I needed to ask what I have to be looking for!

I'll post either tonight or tomorrow with my findings as im working a possible 20 hour shift today to get a few customers jobs out!!!

simple checks don't require being on your back.

get someone to stick it in drive without out of difflock, put it in gear.

stick your head under and see which propshaft is spinning. that's the one with the issue.

if it's the rear, then feel the middle bit of each rear wheel (drive hub member) is one rumbling or spinning. if so, it's probably the member. if you can't tell, pry the plastic caps off and see which is spinning.

come back and report