Two problems related to power assist brake vacuum have been reported for the 1998 Chevrolet Suburban. The most recently reported issues are listed below.
When pressing on brakes they would get hard. Brakes get harder as day wears on. Vehicle would buck if stopped at light or sign. Makes a swooshing sound. Can feel brake pedal fighting back. Have taken to indpendent mechanic, and was informed brake power booster was gone and was leaving no power brakes.
When driving at 55 mph and upon depressing brake pedal brake booster malfunctioned, causing poor braking ability, and resulting in extended stopping distance. Please provide any further details.