Clunking Sound At Front End!

[thatlbeme]

Hi all, not sure if there is a problem and I am going to get a mechanic to have a look when it gets a service done, but I just wanted to have some idea what might be wrong when I talk to him about it.

Its a GTR and the clunking can be heard when I feather the accellerator on and off, just enough to get the car lurching foward and the clunking sound seems to come from somewhere around the front of the gearbox and only makes the noise when in traffic etc and not when the car is accerating smoothly through the gears.

I have checked the engine mounts and gone over everything that I thought might be causing it by jacking the front end up and shaking any moving parts but everything seemed ok.

It have a heavy duty double plated clutch that rattles and caries on like they do but I don't think thats the problem.

If I had to have a guess I would say where the engine joins the gearbox there seems to be something loose or worn there and there is excesive play .

Any thoughts would be appreciated especially if it could be the heavy duty clutch and I might not have a problem at all.

Thanks Ian

[R34_Wong]

Diff/Drive Shaft bearings.

Had the same issue as do many of us with this age car.

[thatlbeme]

Diff/Drive Shaft bearings.

Had the same issue as do many of us with this age car.

Thanks for that, I will have a seach for how to fix it, but if its ok to ask is it a big job and something that could be done at home.

thanks Ian

[thatlbeme]

putting in search for driveshaft bearings has given me a heap more reading to do so thanks, gearbox mount is something that has come up so will need to have a look at that, of to work now but will investigate more tomorrow.

[R34_Wong]

Hardest part will be to find a second hand diff in good condition, which will save you a few dollars else you'll need to spend money reconditioning your existing one.

For me, a few quotes were ok to outrageous depending, but at the end I was lucky and got a good condition diff for $450 and the driveshaft issue done for $400... then you slap labour ontop plus some new bushes/mounts and you'll get your total.

Worth the fix though and I'd suggest you shop around to make sure you're getting the most, don't feel shy to ask as many questions as you can.

Good luck mate.

[thatlbeme]

Can rule out the transmission bracket and cv joints. The noise is almost certainly forward of the gear lever and it might be just to the passenger side of centre. I will read up on how the front driveshaft works as I don't think it is the rear driveshaft/diff from where the noise is. Thanks to the poster that explained how to check the cv joints in another thread.

[thatlbeme]

Think I can rule out the driveshaft splines as per the test of foot on brake and quickly let the clutch partially out in both forward and reverse. No noticable sounds.

thanks to the volvo forum for the test as per pasted below

"its either the driveshaft splines or the dual mass flywheel, its not unusual for the flywheel to make that kind of noise as it does move back and forth about 25 mm or so witha change in load .

To check the drive shafts press the footbeake on and select 1st then Reverse and let the clutch up partialy fairly firmly to put a sharp load through the transmission ( without moving of course as you have the brakes on . do reverse then 1st to reverse the load , if it clicks the first time you say go forward but not the second time without going into R , then its just the driveshaft splines .

If the noise is light when going on and off the throttle at low speed then it's probably the dual mass flywheel ...

Neither is a bad problem ..."