One problem related to brake disc rotor has been reported for the 1998 Volvo S70. The most recently reported issues are listed below.
With approximately 57,000 miles on the odometer I started experiencing severe vibrations when I applied the brakes stopping in a straight line and when turning left at speeds approximating 15-20 miles an hour. The dealer told me that the front rotors were warped because they are aluminum and warp if they get wet when they are hot. Duh! this is florida, how can they not get hot & wet? the rear rotors were replaced at approx 30,000 miles. Deel is currently replacing the rack & pinion steering assembly which apparently caused the severe vibrations when turning left & braking. This car has been maintained at deel Volvo in accordance with the manufacturers guidelines.