Strange Clunk noise at over 100kph

[Eelesy]

This may be harder to describe what im hearing but i will give it a go.

I noticed today while on the freeway, i was in 5th doing about 100kph and when i approached a slow moving car, i had to let off the gas and when i did i heard a clunk sound.
So i played around a bit and figured out if im doin 100 and let my foot off i hear it, and then just slightly depress the loud pedal a tiny bit then release repeatedly, i hear a slight clunk.

It does not seem to happen in 4th or at slower speeds. only around 90-110.

At first i thought someone had pinched my spare bcos the noise sounded like the spare wheel holder swinging around, but only faintly, and coming from the same direction

i have no idea cos i have pulled on everything underneath and nothin seems loose.

Just thought id ask you guys on here before i go to the dealer?

[barraxt]

Wasn't that Volvo speed bump again was it?

[Jitsukablue]

I it the same clunk you get when disengaging in 1st when it's under some load?

[Eelesy]

i dont think so, cos ive heard that one before too.

[Austblue]

Yeah kind of sounds like back lash in your drive train but you'd think that'd be apparent at other speeds also.

[Eelesy]

Yea that was another idea too. i was gonna throw the old highway terrains back on and go for a drive. might be able to hear it better without the tyre noise of the big coopers.

[Stu]

hey saurus, I had the exact same thing start happening yesterday, or at least I only noticed it yesterday. I took my foot of the pedal aproaching a 60 zone from an 80 zone and couldn't hear anything but definatley felt it & after a couple of minutes playing around I found that it only happens in 5th gear and only at speeds above 70kph. When I felt it I remembered this thread and thought I'd share my experiance and hopefully, maybe you've already figured it out?

[Jitsukablue]

We're all going to have to have a play now...

[Stu]

We're all going to have to have a play now...

yep, it gets a bit like that!

strangley enough just walked in the door from a 40km trip down to werribee and I couldn't replicate the situation at any speed?

[Eelesy]

I just got back from a few days away in Dwellingup and i heard it a few times, but to be honest i only hear it when i dont have the radio on.

I dont think its doing damage?? i just wanna know what it is?

[Sportero]

Hi Guys,

I have a Triton Auto. If i step on the accelerator pedal and come off every second and a half or so i hear the clunk everytime i get on and off the accelerator pedal. Reported to dealer and said it was a normal drivetrain noise characteristic of this model they said.

Not too sure how to take that cause they misdiagnosed my van more than once.

I can continuously get my clunk at 20kmph

[Jitsukablue]

I can understand the noise in an Auto, my manual doesn't make this noise, I tried and failed! I don't know anything about the gearbox in the Triton, but generally speaking it could be backlash, which can be fixed with springs (generally speaking, not sure about these gearboxes).
In certain BMW auto gearboxes, you can hear the check valve in the gearbox open and close as oil squirts past it.