VIBRATION UNDER LOAD

[mr nismo]

I HAVE A GU 2.8TD AND IM HAVING A HARD TIME FINDING THE CAUSE OF A VIBRATION (SHUDDER) UNDER LOAD. I HAVE HAD THE UNIS CHANGED, THE TAILSHAFT BALANCED.
I ALSO HAVE A SPARE TAILSHAFT AND IT DOES THE SAME THING WITH THIS SHAFT IN TOO.
I WAS SURE IT WAS THE TAILSHAFT BUT OBVIOUSLY IM WRONG.
IT SEEMS TO BE MOST FELT AT AROUND 80 KMH IN 5TH GEAR UNDER LOAD UP A HILL AND THE CAR WILL BEGIN TO SHUDDER. IF I BACK OFF THE THROTTLE THE SHUDDERING WILL STOP AND START AGAIN WHEN I GIVE IT THROTTLE.
IT DOES IT IN ALL GEARS UNDER LOAD BUT IS MOST NOTICABLE IN 5TH.
ANYONE KNOW WHAT ELSE IT COULD BE?
ITS DRIVING ME NUTS.
OH AND WHICH WAY SHOULD THE TAILSHAFT BE INSTALLED? WITH THE SLIP JOINT AT THE GEARBOX END OR THE DIFF END????

[mav]

my first guess would be a slipping clutch how many kms has it done does it do any hard work (towing ect.)

[Mulisha]

my first guess would be a slipping clutch

yeah i read the above before and couldn't think of what it might be .. and i'm agreeing with mav i reakon it's slipping under load and 5th would put more load i reakon..


Cheers

Rick.

[mr nismo]

its only done 135,000 kms. the clutch doesnt seem to slip? ive towed with it twice, and only a 300kg camper. wouldnt i see the revs rise if it waqs slipping???????

[mav]

try taking off in third or fourth from a standing start with the hand brake full on, lay the boot into it and it should still stall out

[mr nismo]

just tried it and she stalls allright. the nieghbour think im weird!
could it be the diff?

[JWB]

Drive it with the front shaft removed!
then re-install and remove the rear shaft
this might help narrow it down a bit!
Have you fitted bigger suspension lately??

[mr nismo]

wht would the front shaft make any difference? i thaught it just sat there and did nothing untill 4x4 is engaged?
it has a 3" lift but this has been in for a while now

[JWB]

wht would the front shaft make any difference? i thaught it just sat there and did nothing untill 4x4 is engaged?
it has a 3" lift but this has been in for a while now

Sorry! just thinking GQ!
Not that familiar with 2.8 G's does yours have auto hubs?
Just a thought!
You can only try it!

[nastytroll]

good chance its a engine mount or gear box mount posably exhaust mounts or cracked exhaust good luck

[nastytroll]

Also check rear trail arm bushes could be diff housing hammering inside of trail arms

[dirtyGQ]

good chance its a engine mount or gear box mount posably exhaust mounts or cracked exhaust good luck

That is what my vibration was ....a soft gearbox mount and engine mount (edit) it was both.

[rvh96]

sounds like driveline angle to me fit some 15mm spacers under the gearbox x member and see if that helps