Clunking noise on takeoff/braking

adam_rxturbo · Post by **adam_rxturbo** » Fri Oct 28, 2005 11:57 pm

Hey,

I recently pulled out my gearbox and put it back in with a new clutch and new oil... It was running fine for a few weeks, and now, all of a sudden there is a loud clunk/thud coming through the floor around the driver and passenger side footwell. A loud audible clunk which can be felt by your feet through the floor... The noise only really happens with accel/deccel. Clunk is used to only happen every time you go to take off/release clutch, and under heavy braking... But nowadays (2-3 weeks on) its happening a lot, and can even clunk up to 4 times consecutively upon takeoff and braking.

It was suggested to me that it is radius rod bushes. I've checked them out, they are a bit worn, and have a bit of movement in them, but they are still there. The noise sounds like they have completely perished and there is no bush there anymore! And it makes me wonder how it can clunk 4 times consecutively upon takeoff - without any forward/backward suspension movement/rocking... It just happens 4 times when taking off straight and smooth.

Any ideas? Or is it definately a radius rod problem? Or something i might have missed when putting the gearbox back in? I did have some leftover parts, but nothing that i thought would be able to make this much noise!!

Cheers
-Adam

P.s. all engine and gearbox mounts are a-ok

edit: the other thing i just remembered is that the rear diff seemed to have a bit of freeplay in it. sorta borderline backlash, but i didnt think this would make a clunk in the footwell...

Guest · Post by **Guest** » Sat Oct 29, 2005 3:51 am

Engine crossmember is done up tight?

Outback bloke · Post by **Outback bloke** » Sat Oct 29, 2005 4:25 am

If it is the noise I am thinking of then yes, radius rods. Do you notice when you drive if you lift your foot at a steady speed that the direction of the car changes slightly?

adam_rxturbo · Post by **adam_rxturbo** » Sat Oct 29, 2005 7:16 am

engine crossmember was never undone :P but i'll check it next time im under the car.

And brett, it can happen when lightly lifting off and putting down the accelerator while cruising, but it usually needs a bit of a harder suspension movement to make the noise, but it sounds like you're on the right track.

I'm getting some nolethane bushes from xtreme RX as soon as he gets the stock in and i'll see how that goes. But like i said, its baffled me now that it makes up to 4 noises one imediately after the other without shift in suspension (after the initial shift)

Cheers
-Adam

Guest · Post by **Guest** » Sat Oct 29, 2005 1:13 pm

I wouldn't mind a set of Nolathane radius arm bushes either, what's the quote on a set? Xtreme RX?

tim_81coupe · Post by **tim_81coupe** » Sat Oct 29, 2005 1:53 pm

I'd be checking the nuts on the gearbox crossmember. I've had a similar noise and it turned out the nuts were loose.

AndrewT · Post by **AndrewT** » Sun Oct 30, 2005 11:16 pm

Also check all the bushes on the swaybar. I've got this problem in the L series and I can see a couple of split bushes there which are probably causing it.

adam_rxturbo · Post by **adam_rxturbo** » Sun Oct 30, 2005 11:19 pm

had a look under the car again today,

Engine and gearbox crossmembers are both definately tight!

The sway bar bushes is an interesting suggestion, because i noticed mine today - on the ends where it joins to the links - which seem quite worn out, and hard - however still there. Might replace them aswell...

Cheers
-Adam

daza · Post by **daza** » Mon Oct 31, 2005 6:01 pm

there is a flimsy looking rod that goes from the spare wheel carrier to the bell housing "pitch stopper" i've heard it called, i have found it is easy to forget to reconnect...

it allows engine to rock fore - aft if it's not there. ?.

adam_rxturbo · Post by **adam_rxturbo** » Mon Oct 31, 2005 10:04 pm

hey, yeah i know the rod you're talking about. it is definately there, but i havent checked the tightness of bolts and wearing of the bushes. And i took out gearbox from up on a hoist - so engine remained in place.

Cheers
-Adam

adam_rxturbo · Post by **adam_rxturbo** » Thu Nov 03, 2005 6:25 pm

another thing i thought of recently.. was drive shafts... I know the boots are worn and nearly split in my current ones. Is it possible that a worn CV shaft would be able to make a similar clunk noise? which would make far more sence in relation to the 4 consecutive clunks rather than suspension movement...

Cheers
-Adam

Guest · Post by **Guest** » Thu Nov 03, 2005 8:37 pm

Another stupid question . . . all the fasteners on the radius rods are tight?

I'd go with some new Nolathane radius arm bushes - they're pretty cheap from Black Box!

Kev · Post by **Kev** » Sat Nov 05, 2005 1:55 pm

AndrewT wrote:Also check all the bushes on the swaybar. I've got this problem in the L series and I can see a couple of split bushes there which are probably causing it.

The easyest way to check the swaybar bushes is to take it off altogether. I know one of the WA crew never uses one at all.

adam_rxturbo · Post by **adam_rxturbo** » Sat Nov 05, 2005 7:53 pm

ok, bit of an update. I got the car up on the hoist again yesterday arvo, and checked the tightness of everything i thought was related - except one thing mentioned in a moment. Crossmembers, radius rods, pitch rods, swaybars - the lot. Nothing was loose at all.

Swaybar link bushes do look to be quite worn out and are squished up to pankakes

But i've ordered them up from xtremeRX so will replace them asap.

The other thing i only just thought of while replying to that liberty idea thread... Is that i had the driveshafts out in the front and back many times, and had also rolled the car on the ground without driveshafts in them - with the wheel bearing making some clunking noises while it was rolling (since it wasnt located by the driveshaft)... And that made me think. What if that little thrust washer between the knuckle/bearing and the driveshaft wasnt quite sitting right, and i had tightened the nut on the end of the driveshaft like that, and now it has moved around a little and is causing the clunking noises?!

Is there any proper proceedure for fitting up the driveshafts through the hub and tightening the nut on the end properly (in regards to torque, i just did it up with the rattle gun to about 100 ft/pound - wheel nut torque). By way of proceedure, i mean by locating the thrust washer properly, and spinning the wheel/driveshaft or something to make sure its sitting properly? Or is it just a whack together job - like i did?

Cheers!
-Adam

BaronVonChickenPants · Post by **BaronVonChickenPants** » Sat Nov 05, 2005 9:46 pm

I'm pretty sure the the correct torque for the hub nut is 160ft/lb, try tightening it more.

Jordan.

PeeJay · Post by **PeeJay** » Sun Nov 06, 2005 9:56 am

Tighten it with a 1.5m extension on a breaker bar. And jump on it a bit.

adam_rxturbo · Post by **adam_rxturbo** » Sun Nov 06, 2005 8:37 pm

ok, checked out the drive shaft nuts today, and they are definately still tight, and the split pins are still in them and are in perfect condition - no squashing/bending/evidence of nut undoing. So the nuts are still tight... however is there any correct seating of the thrust washer? it SHOULD still have been located in the right direction...

I've just known that for some 4wd's, the thrust washer can sit slightly out of place, and will usually prevent a circlip being able to fit onto the drive shaft once all the hub has been installed...

I also checked for bearing play while i was at it, and there doesnt appear to be any movement in the wheel/bearing.

Should be getting those radius rod bushes from Xtreme RX soon!

Cheers
-Adam

adam_rxturbo · Post by **adam_rxturbo** » Wed Nov 23, 2005 10:31 pm

once again, for anyone interested - an update.

changed over the gearbox for an AWD one on the weekend - with different front driveshafts. And now, the clunking noise is completely GONE! Havent touched anything else! Original radius rod bushes are still in there!

So i guess it was either a clunk in the gearbox somewhere, or the worn out driveshafts. (the radius rod bushes did seem a bit far out to make the noises i were hearing

)

Only problem now is that i've got gearbox noise

- see to other threads if you're really interested hehe

ok enough out of me.

Cheers
-Adam

Subarooted · Post by **Subarooted** » Wed Nov 23, 2005 10:54 pm

those sort of clunking noises sound like the typical CV joint wear noises that my car gets when the CV are worn. Glad the problem is fixed