Having problems with your 1997 GMC Yukon ?
Brake pedal goes to floor by itself when truck is started and brakes are locked
The vacuum booster for the master cylinder should be looked at. ive done this for over 20 years and i cant say ive ever heard of this. does this occur ONLY when the truck is started? do you have a pedal when the truck is off? please respond.
Repair Help & Product Troubleshooting for 1997 GMC Yukon
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