rumble noise from boxster

[squashkid0]

Need advice. I have a boxster 2002 3.2s. At very low speeds ( 1-15mph) there is a "rumbling noise" like a vibration coming from underneath.Especially noticeable when driving over uneven surfaces on the road. Its not the engine mounts or the shocks as Ive had them replaced recently. Not a metalic sounding noise either ie exhaust heat shields as Ive eliminated this. Its a lower end, non metalic noise. Anything above 15mph and the noise goes away. Apart from this the car drives like a dream. Does anyone have any idea what it could be? Its been evident for the last 2 years now. Please help

[Mutt]

Wheel bearing. Does it increase with cornering?

[squashkid0]

dont think its the wheel bearing and it doesnt increase when cornering. The noise is the same level until about 15-20 mph regardless of whether i drive it in a straight line or turn the steering wheel

[lordlee]

Could be the early signs of the coffin arms failing my Box was making a similar sounding noise before one of the bushes failed. You could take it to a bumpy road and drive it low speed over the bumps and listen for any clonking as that would indicate bushes. I have to say though that most rumbling will be early stage wheel bearings.

[sandman77]

lordlee said:

Could be the early signs of the coffin arms failing my Box was making a similar sounding noise before one of the bushes failed. You could take it to a bumpy road and drive it low speed over the bumps and listen for any clonking as that would indicate bushes. I have to say though that most rumbling will be early stage wheel bearings.

I was under the impression that failing coffin arms begin to squeak rather than knock or rumble. A knocking noise at low speeds is usually the (forked) control arms.

[edcs]

The anti-rollbar bushes on my '02 Boxster seem to be on their way out, they make a rattle at low speed too. I guess that doesn't help much, but the front suspension does seem to get noisy when these cars get to this sort of age so it's probably worth jacking it up and taking a look.

[squashkid0]

Thanks to everyone who has replied to my question. Hopefully I can get the problem resolved.