Volvo: RPM needle bounces in my 940, high mileage, maintance

Question
My wife has notice that when she is driving my Volvo that the RPM needle bounces. I drove it the other day and finally saw what she was saying. It doesn't happen all the time and the tran doesn't slip. The only thing is for the inspection this year they had to do some work to the odometer because that was broken. Should I worry that the trans is slipping or is it just the RPM tac going bad.

Answer
Corey,
Since the car has high mileage I would drive and take note of the shifting and feel of the trans, to make sure that it is not slipping. Is the fluid burnt and dark? That would be a good indicator that the trans has slipped in its maintance and need attention. If only the tach seems to be erratic then I would just live with that small quirk.