Something to shake the car

[swd80]

Is there such a machine that you can put your car on it and it simulates bumps in the road? So a mechanic can get under the car and find the source of a rattle?

My car (Mercedes W204 C320 CDi Sport with dynamic suspension) has had a really annoying rattle for a while now. The sound is a bit like when you're towing a small trailer. It has had replaced front springs (due to a big pothole) and new front shocks (one was leaking) but the noise continues. My local independent Mercedes garage has checked all the suspension, heat shields, exhaust etc etc but can't find anything amiss.

I'm aware of chassis ears that can be attached to the car - does anyone have experience of these and are they useful to get to the bottom of a problem such as this?

Any advice gratefully received!

[Happy Jim]

I walked past my local garage and did a double take when I saw a car inside shaking itself to bits - turns out it's their funky lift thing that they use for MOT's - does exactly what you need and allows the MOT tester to view all the bushes for wear etc.

Jim

[swd80]

Happy Jim said:

I walked past my local garage and did a double take when I saw a car inside shaking itself to bits - turns out it's their funky lift thing that they use for MOT's - does exactly what you need and allows the MOT tester to view all the bushes for wear etc.

Jim

I don't suppose you know what it's called? Would help when trying to find one!
Many thanks

[Penelope Stopit]

Shaker plates will do the job https://youtu.be/3iczgZgUsrI

http://www.gemco.co.uk/product/bm53000-commercial-...

[stevieturbo]

Shaker plates MOT use may or may not help.

Their motion is limited in certain plains, as they're largely only for checking for play in joints.

There is another test for shock absorbers/suspension, but you wouldnt be able to get under the car when this one is in use, as all the ones here are ground based as opposed to on a ramp like the shakers.

Really the noise needs tracked down by experienced ears/mechanic. Sometimes the smallest things can make the most noise !

Whether a slightly loose cradle bolt or bolts, work anti-roll bar bushes etc etc And the likes of those wont show up on shakers or shock testers.

[CarsOrBikes]

Description does sound like bottom coil of a rear spring sitting in the arm or rear arb link, or damper top mount. The ATL one man test rig is only a lateral test, but still something to try. It's only used on front suspension in test, but you could put the rear wheels on the plates and see what it produces. Only one plate moves, the osf, but drags the other side to a degree. I guess you've driven it with someone in the back or boot?