Vibration from Rear when idling

[ba3bas]

Hi All

I have an intermittent rumble/vibration from the rear of the car.

If i'm in D when foot or handbrake up, there an on/off vibration like a deep rumble.

Soon as the car is i neutral or I drive off, it goes away.
Car drives smooth no issues at all. No cornering noise so i know it's not suspension or bushes as Inspection 2 done recently and all OK.
Mention of acceptable movement on exhaust but it seems sturdy .

Any ideas before off to dealer?

Concerned it might be a gearbox bush or something.

 

[bcworkz]

I think you are getting resonant vibration of the back box under a particular engine load. You should be able to feel this by holding something against the box as soon as the vibration starts. If this checks out, fresh suspension rubbers and isolation bush could change the resonant characteristics enough that it doesn't happen any more.

 

[ba3bas]

Hmm, not sure it's the exhaust.

Very hard to replicate the issue on prompt.
When the coilovers are being fitted i'll have better access

 

[Bad_Pritt]

sorry, can't resist:
Shake that ass!

Noise coming from where exactly? Bumper area? Boot? Bottom of the car? Top of the back end?
Might help to locate the problem?