Clunk at Back

Hi all. I hope some of you folks will be able to hepl with this.
I have a 1995 defender 110 158K miles, mechanically still fine.
The hind quarters emit a loud clunk when pulling away, also on the change from first to second. It is possible to avoid with careful use of clutch and loud pedal. I've has trans box reconed last year halfshafts are fine as are U/J's. I've had a poke about on the threads and the concencus apprears to be the a frame ball joint and or its associated bushings. My concern: is it possibly slack the rear diff. Its a Salisbury?
All answers gratefully received
Thanks Jerry

My money would be on the a-frame ball joint.

And the winner is ..



A frame ball joint.

yes i third the A-frame ball joint. the nut may be fully tight but not tight against the axle mout. i had to add a larger washer to allow it to tighten fully

Cheers for the rapid replies guys. A frame job the weekend then. Will use the step by step guide provided by Buster.
Thanks again Jerry

If its not the A-frame ball joint it will be the input gear and mainshaft that have worn and will need to be replaced. If it is a loud clunk when taking up drive and when changing gear, that sounds like the symptoms.

atn90 said:

If its not the A-frame ball joint it will be the input gear and mainshaft that have worn and will need to be replaced. If it is a loud clunk when taking up drive and when changing gear, that sounds like the symptoms.

Click to expand...

Mine does this, and it is not the A frame balljoint, I can avoid it mostly by careful clutch work - but today noticed it a lot on the motorway at about 65-70 mph, when pulling on and off the power.

What is the solution? I am guessing its not cheap, nor and easy DIY job?

I had exactly the same problem, what happens is the mainshaft of the gearbox wears on the input gear off the transfer box. You then get a lag in power transfer. Hence the 'clunk'. Unfortunately it is a gearbox out job to replace the mainshaft. And then a transfer box out job to replace the input gear. However when you have the job done make sure you put a cross drilled input gear in as this then greatly reduces wear in the future. It is a common problem that happens in all old landy's due to them now packing the miles on and then the parts wearing.

atn90 said:

I had exactly the same problem, what happens is the mainshaft of the gearbox wears on the input gear off the transfer box. You then get a lag in power transfer. Hence the 'clunk'. Unfortunately it is a gearbox out job to replace the mainshaft. And then a transfer box out job to replace the input gear. However when you have the job done make sure you put a cross drilled input gear in as this then greatly reduces wear in the future. It is a common problem that happens in all old landy's due to them now packing the miles on and then the parts wearing.

Click to expand...

thanks, is there a DIY guide anywhere for this work? Or is it beyond DIY??

Yeah as long as you have got the equipment to do it and you can buy all the parts from ashcroft transmissions.

Digging around I found this useful link, it doesnt look such a hard job to replace the gear if its worn, has anybody on here ever done this in situ on a defender?

Also I cant see any mention of replacing the worn shaft, any advice on how to do that too?

I might give this a go over the next couple of months if I can track down the parts at a reasonable price.

https://docs.google.com/Doc?docid=dhfmtstj_0ghdpj7jh&hl=en

johnnyoxford said:

Digging around I found this useful link, it doesnt look such a hard job to replace the gear if its worn, has anybody on here ever done this in situ on a defender?

Also I cant see any mention of replacing the worn shaft, any advice on how to do that too?

I might give this a go over the next couple of months if I can track down the parts at a reasonable price.

https://docs.google.com/Doc?docid=dhfmtstj_0ghdpj7jh&hl=en

Click to expand...

easy enough to check, ring of bolts and inspection cover.
all you do is pur boxes in neutral and jiggle it to get gear out, cross drilled reduce input shaft wear

Gearbox output shaft is more involved.

Also check A frame ball joint and uj's

my money's on the drive flange ,common fault on 110's

scuse my ignorance wayne, but where is the drive flange?

defenderwayne said:

my money's on the drive flange ,common fault on 110's

Click to expand...

it's attached to the half shaft,behind the plastic cap in the centre of the road wheel is a circlip,that holds these to the halfshaft,these wear as its not a solid joint,remove the circlip and five 17mm bolts and they come off,new ones arn't that expensive,see link below

FRC5806 Drive flange - rear axle to KA930455

thanks, I am with you now, I removed this when I changed a wheel bearing a while back, whats the best way to establish if its worn? Jack it up and wobble it I guess? With diff lock engaged? Would that work?

yes,jack it up and remove the plastic grease cup,gently rock the wheel back n forward,my guess is you'll see some movement,and you don't have to lie on your back to replace em .

trailing arm bush is another contender, although I'm sure my main clunk at the moment is the gearbox mainshaft to transfer box intermediate gear.

replacing the main shaft on the lt77 is a big job by the looks of it, and does require some specialised tools :/

the clunking sound, sounds simler to what was up with mine. turned out it was the traling arm to chassis bush. it was pulling back when accelerating off "clunk" and pushing when breaking "clunk". you could grab the trailing arm an rock it and you could hear the knocking sound. replaced them and the soudns gone. give that a bash. im no expert but it worked for me

hope it helps

Ben

When I did mine, it was the trailing arm to axle, and it was causing the axle to 'help' with my steering whenever changing gear of starting to accelerate or brake too!