1. Welcome To GMTruckClub.com!

    The #1 Chevy Truck Forum Online
    Online since 2004, we are the #1 Chevy Truck & SUV forum and user community. If you have any questions about your Chevy or GMC Truck, SUV or Crossover, or just want to connect with other GM owners and enthusiasts around the world, you've found the best place on the internet to do that.

    Join Today ~ It's Free
    Registering is Free and Easy! Hope to see you on the forums soon!

Brake issues on 99 Suburban

Discussion in 'General Chevy & GM Tech Questions' started by Mack46, Nov 23, 2011.

  1. Mack46

    Mack46 New Member

    My suburban brake pedal has started sinking to the floor on most stops. When it sinks the brake light will come on but if I release pressure and press again it will be pretty stiff. What would cause this, I have bled the system and had the system flushed. I am not losing fluid so could it be the master cylinder? Any help would be appreciated.
  2. KidHauler

    KidHauler Epic Member 5+ Years 500 Posts

    Welcome to GMTC.
    Provide us with some more info of your truck;
    1/2 or 3/4 ton? (does it have hydro-boost)
    Have you scanned for codes? (anti-lock module)
    Have the pads/shoes been checked?

    This place is full of knowledgeable folks.
    Good luck,
  3. Mack46

    Mack46 New Member

    It's a 1/2 ton 2wd Suburban, nothing came up when we ran the codes and no I haven't checked the pads yet. I replaced the pads not too long ago though... This is my wires car so I rarely drive it but did have the opportunity last night. First push is very loose sometimes will catch and have good pressure but most of the time the pedal goes to the floor but the car does stop. If I release the pedal is going to the floor and release the pedal and push again it always has great pressure. Like I said before the break light only comes on when the pedal goes to the floor and then will go off by itself. Thanks again.
  4. 2COR517

    2COR517 Epic Member 5+ Years 1000 Posts

    Sounds like the master cylinder is leaking internally

Share This Page