RepairPal Certified shops can diagnose and repair your 1990 Chevrolet R1500 Suburban. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
it is vacuum activated by the control head. it is under the left side of the dash by the gas pedal. it moves for all 3 positions but needs to be checked by someone who knwos the system.
Roy
thank u very much. larry