Clonking transmission when in traffic.

[carl350i]

Hi,

I have a Touareg v6 petrol 2004 with 80000 miles on it. It drives lovely but it make a clonk when in traffic, I'll try to explain.

When I pull away at a normal speed, it's smooth with no noises or clonks.

When I'm in traffic and it pulls away slowly you can hear something clonking underneath in the transmission system, it's almost like a lot of backlash in the driveshafts or prop. The noise doesn't always seem in the same location.

Any thoughts appreciated.

cheers.

[xila]

A lot of Touaregs after a few years suffer prop shaft issues. Well discussed in mytreg forum with different solutions.

[Radio89]

Have you checked the engine mount at the bottom of the engine? When the rubber bushing disintegrates it makes a clonking noise when under a certain load. For example when you are moving off in traffic there is a lot of torque being applied so the engine is trying to twist in the engine bay. The bushing stops this torque so if the rubber has fallen out due to age and fatigue every time you apply the most torque to the engine it will try to twist and therefore clonk against the engine mount. Also with the engine moving that may affect the position of the propshaft and therefore produce the illusion that the sound doesn't happen in the same location each time.

I know you mentioned above it tends only to happen when already moving but depending on what way the rubber is situated in the bushing along with the inertia of the vehicle it can cause an intermittent clonking. For the sake of a quick 60 seconds inspection you can at least rule it out as a possible cause. If you put the car in neutral and have someone stomp on the accelerator a few times as you look in the engine bay you should be able to watch the engine try to move (the bottom of the engine wants to move towards the rear of the vehicle) due to the torque affect mentioned above. If you are lucky(?) you will hear the clonking once every few pedal stomps, otherwise just watch to see if the engine is moving excessively in the engine bay. If you can, look at the movement of the engine from under the driver or passenger wheel well whichever gives you a better view of the engine mount.

Good luck
J

[carl350i]

Hi,

Thanks for for the ideas.

I gave it a service a couple of days ago, and whilst the under tray was off I checkedthe engine mounts which are all in really good condition.

I had a good look along the propshaft and this too looks in really good condition, I gave everything a good pull and push.

As I say it only seems to happen in traffic when I let the car roll under its own steam without using the loud pedal. Its like the car wants to change from 1st to 2nd but it's going so slow that it hangs onto the change, and make a noise and a clonk.

cheers.

[rowdy-999]

Hi,

Thanks for for the ideas.

I gave it a service a couple of days ago, and whilst the under tray was off I checkedthe engine mounts which are all in really good condition.

I had a good look along the propshaft and this too looks in really good condition, I gave everything a good pull and push.

As I say it only seems to happen in traffic when I let the car roll under its own steam without using the loud pedal. Its like the car wants to change from 1st to 2nd but it's going so slow that it hangs onto the change, and make a noise and a clonk.

cheers.

Auto I assume? Change the fluid. If that doesn't work it could be a valvebody solenoid fault.