LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 1990 >> Forward Control 7.4 N, Automatic, 475/M40 >> Repair and Diagnosis >> Brakes >> Mechanical - Hydraulic >> DISC & DRUM (C, G, K, P, R & V Series) >> Testing >> Hydro-Boost Testing >> Hydro-Boost Functional Test

Hydro-Boost Functional Test

  1. Make all preliminary checks. Place transmission in Neutral and stop engine. Apply brake several times to deplete accumulator reserve.
  2. Hold brake depressed with medium pressure. Start engine. Brake pedal should fall slightly, then push back against foot. If no action is felt, booster system is not operating properly.