This isn't a question on my Volvo, but on Maxima, but I get better technical responses from this board, so hope you don't mind my posting here.

The car developed engine vibration that fairly noticeable at stop. I initially thought it was engine or tranny mount, but a reputable mechanic told me it's the timing belt that gets stretched when warmed up, and it's the balance shaft causing the vibration.

Symtoms are - at full stop, I feel vibration thru steering wheel, but only in driveable gear, i.e., R/D/2/1, but not in P or N. It happens only after the engine warms up as well. Vibration is not noticeable when the car is moving.

The mechanic tells me that it's normal and I shouldn't worry about it. The belt was changed only ~10k mi. ago. I believe I started noticing it ~5-7k mi after the change.

My question is, is it really normal for the belt to get stretched? Would it indirectly cause other problem if I don't get it fixed? How come I never had it happen on my Volvo or any other car I had previously - sloppy belt installation?

Thanks in advance.