[Rich22]

Hi can anyone shed some light on this, new 08 gt premium auto makes a metallic like noise from passenger side rear wheel or drive shaft, sounds like a stone in the tyre hitting the road on every rotation worse at around 25mph and only does it when coasting. Done it from new had new diff with no improvement.

[play4life]

This sounds like it could be a loose lug nut...

[BKid]

Check your u joints.

[The Greek]

Have you tried jacking the rear wheels off of the ground and placing the trans in gear and checking for the noise from underneath? Please keep safety in mind while doing this, use jack stands and wheel chocks. You may get an ABS light to come on because the front wheels aren't turning, just get the light turned off after you're done.

[NavySVO]

What does the dealer say (assuming you have taken it to them)

There have been problems with the '05+ differentials. Not all, but a fair amount.

[Rich22]

My dealer is sorting the problem out i am just trying to give them a clue as to whats up, changed the diff with no improvement, have jacked the back up and to me it sounds like a drive shaft or wheel bearing which is strange on a brand new car. When jacked up there is top to bottom play in the wheels both sides! is this normal? also when wheels are off the wheel lugs are loose, i dont know if this is normal stuff or not!