Transmission hell.....

[alex and harry]

Ok bear with me a very green defender owner. We own an 89 defender 90 pick up with a 200tdi engine from a disco. 205k on the clock. Me and my lad went on a very easy off road day all organised. Anyway as we went up a hill we had a big clunk whilst in diff lock and loss of drive, it moved only with handbrake on!! Then it spat the cogs through the rear diff casin!! We have replaced the rear diff. However it now drives like a bag of spanner’s. After about 400m it shudders and when we slow down and turn it clunks and clanks from the from and I sh1t myself!! Where do I start, could it be the front half shafts, or the gear box shaft thingy in the transfer box. Help please in simple terms cheers.

 

[Wimblowdriver]

I sh1t myself!! Where do I start

Nip down to the shop and get a roll of Andrex.

 

[alex and harry]

Nip down to the shop and get a roll of Andrex.

Thanks for the advice. Once I'm all cleaned down what about my landy?

 

[freelance]

Have you put a different ratio diff in by mistake ?

 

[tottot]

How did you get home,was it with the hand brake on ?
Because if that was the case then your difflock was not working.
You can drive a landy that has lost drive to one axle in diff lock no problem [ best done with shaft to broken axle removed and drive flange bolts removed]
Drive with hand brake on and center diff may be damaged.

 

[tottot]

Ha freelance,did that with a mates trialer the other day.We did not realise it had series diffs and put one in from a disco
Only had to drive ten yards to figure it out,dragging its arse as it did

 

[alex and harry]

Hi guys, yes it drove back with handbrake on so what' the centre diff the transmission box? I took rear prop off for a test drive and it still hanging out it' ar5e...
I' going to Jack it up today and teat the diff lock to see if it' the diff??

Any ideas or help are hugely welcome.
Also how the he'l do you know if the rear diff repla wmwnts ratio is different to the original.
Thanks in advance.

 

[jamesmartin]

Hi guys, yes it drove back with handbrake on so what' the centre diff the transmission box? I took rear prop off for a test drive and it still hanging out it' ar5e...
I' going to Jack it up today and teat the diff lock to see if it' the diff??

Any ideas or help are hugely welcome.
Also how the he'l do you know if the rear diff repla wmwnts ratio is different to the original.
Thanks in advance.

diff lock isnt engaging which is common with linkage seizing or wearing too loose,id check front axle as well, yours should be a 10 spline 3.54 diff if original a 3.54 diff will have 13 teeth on the pionion

 

[tottot]

The center diff at the front end of the transfer box allow the front and rear axle's to turn at different speeds on the road.When off road in slippery conditions it is then locked so drive is solid to both axles an they go at the same speed to improve traction. [ Standard axle diffs are open at all times but lockable ones can be fitted to improve traction further in very difficult conditions.]
The center diff will not have liked been driven very far with the hand brake on,it's not what it was designed for.[ small gears and bearings will have been spinning very fast and getting rather hot.]

 

[alex and harry]

Ok thanks so I check the front axle do you mean take the wheels off where the half shaft is etc? And then take the front diff off and check for wear? Also the centre diff do I need to take this to bits and check for wear.
Sorry guys for what might sound like daft questions but me and my son are novices at this.

Cheers.

 

[tottot]

Start by jacking the front axle and then push,pull and rotate wheels by hand both in straight ahead and turned positions. Listen and feel for unusual clunks clatters ect from the axle,hubs,prop and front output of transfer box and report back.

 

[dag019]

Ok thanks so I check the front axle do you mean take the wheels off where the half shaft is etc? And then take the front diff off and check for wear? Also the centre diff do I need to take this to bits and check for wear.
Sorry guys for what might sound like daft questions but me and my son are novices at this.

Cheers.

If you have already rebuilt the rear axle so that is now fully working all that is left is transfer box and front axle. I would check the front first as that is straight forward and the same as you have done on the rear. So check the half shafts, drive flanges, CV's and diff for play and wear. But from your description I agree with tottot that is it more likely to be transfer box related and be a problem with the center diff. Unfortunately I do not know how you would repair this. To check the centre diff you need to try and free of the linkage so you can engage the diff lock.

 

[alex and harry]

Ok guys here goes.
This afternoon my lad and I have investigated our defender and have found the following.
We jacked up the front. Whatever we did with the dif lock the wheels moved but if we held the prop shaft the wheels wouldn't move. So then again whatever we did with the diff lock and we started it up the landy tries to drive off the jacks. A you tube video said in bottom right it should just drive the wheels round. So we then took the rear prop off the wheels turned under aceleration. So we took it through the gears on the jacks and in third and fourth it sounded like sh1te and the whole gear box area was shaking and shuddering . Not good.
Any ideas, I fear it's the diff lock / transmission which is locked in.
Note the diff lock light did light up and switch off when I was playing around but seems like whatever I did with the stick made no difference to the actual outcome/drive....
Any ideas. Strip down transission box and garbox???
Thanks in advance guys.

 

[tottot]

It does sound as if the center diff is the problem.With the rear prop off and hand brake off and diff lock out all that should happen is the rear output and handbrake drum spins up and perhaps the jacked up front axle turn slowly when driven.
The center diff is in the housing behind the front prop.

 

[alex and harry]

Hi is it possible to remove the centre diff (is this the transmission box?) Without dropping the gearbox. The gearbox is an LT77 (reverse is left and up).
If so how can I do this?
I removed the pto plate and there is a bit of play and loads of gunk looks like new oil needed. Is that ok and mean the transfer box. Is ok?

Thanks in advance.

 

[jamesmartin]

no you need to drop the t/box off. remove sump plate ,hi/lo housing ,detent plug 6m allen screw,remove intermediate gear ,remove front output housing diff will come out with it or pull out after

 

[tottot]

Why have you removed the PTO cover? if the shaft/intermediate gear had failed you would have no drive at all. As in previous post the center diff is in the front output behind the front prop shaft.

 

[alex and harry]

Thanks James. Is there a thread that describes or shows how to do this as its lost me. Does that mean the transfer box comes off with the gear box in situ?

Tottot I only removed the pto to be inquisitive, we really are learning from entry level so please bear with any daft things we do.
Thanks guys.

 

[jamesmartin]

you need to separate t/box from g/box, that can be on the vehicle or on the floor

 

[alex and harry]

Great stuff where's the best guide to understand how to do this?