Started today, has got slightly worse...

up to 50mph accelerating is fine.... i let off the gas and its starting to vibrate and i can hear a slight low toned clunk/thumping sound the lower the speed goes...

any ideas?

 

Possibly drive shaft U joint.
Dave

 

Another suggestion, there's 2 rubber donut couplings on the prop. Check these out.

Where does it sound like it's coming from, and can you get the car on a ramp?

 

The vibration at highway speed letting off the gas feels like its coming from the left side of the car. At lower speeds as its decelerating, the is an obvious low thump from the rear.

Update:

Its the passenger rear wheel bearing.... Anyone know if there's a DIY guide? They wanted $600 to replace it.