Transmission clunk!

hi one and all. im new on here but could really do with some help.
my 300 series disco (1995) has one hell of a clunk when i change gear or let off the throttle and it goes into over run, will also do it sometimes if i get back on the gas. i can really exaggerate the problem by rocking it from 1st too reverse. both the prop's are fine and ive had them off one at a time to see if i could isolate the problem to one of the diffs, but it makes no difference.
so that has led me to the pricey part of my truck that is the transfer and gear box! i understand the output spline on the gearbox and transfer union can wear.
now, the million dollar question is can this be fixed or am i looking at a pair of new box's? or is there something else i should try?
Big problem being that im trying to sell the truck but dont really want to chuck loads of money at it. HELP!!!

Whats a truck?

This noise is very common and very often caused by a worn 'A' frame ball joint, on the rear suspension just above the centre of the rear axle casing.

To replace it you need to jack up the chassis to give working room above the axle.


Dave

thebiglad said:

This noise is very common and very often caused by a worn 'A' frame ball joint, on the rear suspension just above the centre of the rear axle casing.

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:welcome2::welcome2::welcome2:

They can often be very neglected!

The photo doesn't do it justice but mine had a gap of 2-3mm around the ball and was risking popping out.

nathan5346 said:

Whats a truck?

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is that a serious question!!?

Can you feel the clunk through the shift lever, or just hear it ?

Possibly a failed mounting?


For those who believe, no explanation is necessary.

For those who do not, none will suffice.

thanks for the advice on the A frame ball joint. i will have a look at it.
its just that when ive been underneath while someone else was shifting it back an forth, the sound seemed very transmission orientated. lets hope your both rite though as the A frame ball joint will be much cheeper and easier. thanks

sedgey said:

thanks for the advice on the A frame ball joint. i will have a look at it.
its just that when I've been underneath while someone else was shifting it back and forth, the sound seemed very transmission-orientated. Let's hope your both right though as the A frame ball joint will be much cheaper and easier. thanks

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Cheaper yes, easier - well I'll let you decide

Hi all, i'm new here too ...
I've got a '99 T Plate Series 1 Disco (Auto) with a transmission clunk too....yay (I've joined the club) !!!
I've changed the A frame balljoint for a complete balljoint/bracket unit from Paddock (A Britpart unit) and i've still got the noise, any suggestions? It seems to be loudest when going from Drive to Reverse and is quite loud from the outside.
Got to go underneath it today as the brakes failed the other day and all the discs and pads need doing (I think it's had a neglected previous life).....oh the joy of owning a Landy!
Answers on a postcard (or here) Please....

landypug said:

Hi all, i'm new here too ...
I've got a '99 T Plate Series 1 Disco (Auto) with a transmission clunk too....yay (I've joined the club) !!!
I've changed the A frame balljoint for a complete balljoint/bracket unit from Paddock (A Britpart unit) and i've still got the noise, any suggestions? It seems to be loudest when going from Drive to Reverse and is quite loud from the outside.
Got to go underneath it today as the brakes failed the other day and all the discs and pads need doing (I think it's had a neglected previous life).....oh the joy of owning a Landy!
Answers on a postcard (or here) Please....

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Hi landypug and welcome to LandyZone.

Re the clunk when selecting gears on your autobox car, do you firmly depress the footbrake BEFORE selecting gears? They all thump a little bit when taking up drive, but this can be reduced if you press & hold the foot-brake, before selecting gear.

Re discs and pads alround, not a hard job but not as quick as on a std car.


Good luck
Dave

I've always had the clunk from the transfer box when selecting reverse so that's 24 years of clunks, it can't be a fault with the box because when the RRC went over to a Borge Warner transfer box the clunk was gone. So I would say don't worry "they all do that sir"

If you have a thump when selecting drive then there is a problem, just a small one maybe like the engine idle speed is a fraction to high, but then that maybe a diesel thing, some say that that engine doesn't suit an auto.

thebiglad said:

Hi landypug and welcome to LandyZone.

Re the clunk when selecting gears on your autobox car, do you firmly depress the footbrake BEFORE selecting gears? They all thump a little bit when taking up drive, but this can be reduced if you press & hold the foot-brake, before selecting gear.

Re discs and pads alround, not a hard job but not as quick as on a std car.


Good luck
Dave

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Hi Dave, yes I do tend to hold the brake pedal, as it's an eager bugger to get going. The noise sounded like the type that the A frame joint makes, like a clunk with a thump. I was very dissapointed when I fitted the new joint and it still did it! The brakes, other than being a bit long winded shouldn't be a problem.it's nice to finally find a car that parts are cheap for though....

discool said:

I've always had the clunk from the transfer box when selecting reverse so that's 24 years of clunks, it can't be a fault with the box because when the RRC went over to a Borge Warner transfer box the clunk was gone. So I would say don't worry "they all do that sir"

If you have a thump when selecting drive then there is a problem, just a small one maybe like the engine idle speed is a fraction to high, but then that maybe a diesel thing, some say that that engine doesn't suit an auto.

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Hmm, have thought that maybe the engine idle is a bit high, may knock it down a bit and try again. Amazingly, all the minor niggles my Disco has, haven't put me off ever owning another one. If I find a fault, i'll post up what it is....you never know!

Check the Clunk isn't coming from the front Diff , lay under Disco and grab prop shaft rock it from side to side there will be a bit of excess backlash, you will hear the clunking from the Diff. Its not that hard a job changing the Diff , take prop shaft off Wheels off take drive shafts out, undo nuts around Diff, then simply lift out Diff . Go to nearest Landy Breaker and reverse process Job done , Remember oil and beer