1. Welcome to Tacoma World!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tacoma discussion topics
    • Communicate privately with other Tacoma owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

Brake Pedal Vibration (2011)

Discussion in '2nd Gen. Tacomas (2005-2015)' started by knphee, Oct 23, 2010.

  1. Oct 23, 2010 at 9:29 PM
    #1
    knphee

    knphee [OP] Member

    Joined:
    Aug 5, 2010
    Member:
    #41295
    Messages:
    20
    Gender:
    Male
    Calgary, AB CANADA
    Vehicle:
    2011 AccessCab TRD OR
    Does anyone else feel this on their new trucks?

    The best way to describe it is a slight (but noticeable) one second vibration/pulse when the brake pedal is depressed usually 1/4 way down. It doesn't happen all the time (which makes extremely annoying). The truck only has 500kms on it !

    I've taken it back to the dealership but of course, they assure me it's 'normal' :notsure:. There wasn't another 2011 on the lot, but I'm sure the truck I test drove 2 months ago didn't have this. I didn't push the issue with them but it is documented that I raised this concern.

    I've spent some time searching online and it seems others have reported the same issue. Some say it's normal (related to ABS), others have indicated the brake booster could be a problem.

    Any thoughts?
    Thanks,
    KN
     
  2. Oct 23, 2010 at 9:38 PM
    #2
    Taco11

    Taco11 Well-Known Member

    Joined:
    Sep 11, 2010
    Member:
    #43080
    Messages:
    175
    Gender:
    Male
    First Name:
    Chris
    Seattle WA
    Mine does it too. Im not too worried. I think it has something to do with the different brake system on the newer trucks. Which I also believe is because of the A-TRAC system.
     
  3. Oct 23, 2010 at 10:11 PM
    #3
    knphee

    knphee [OP] Member

    Joined:
    Aug 5, 2010
    Member:
    #41295
    Messages:
    20
    Gender:
    Male
    Calgary, AB CANADA
    Vehicle:
    2011 AccessCab TRD OR

    It's an AccessCab TRD OR
     
  4. Oct 23, 2010 at 10:19 PM
    #4
    knphee

    knphee [OP] Member

    Joined:
    Aug 5, 2010
    Member:
    #41295
    Messages:
    20
    Gender:
    Male
    Calgary, AB CANADA
    Vehicle:
    2011 AccessCab TRD OR
    This is a cut and paste from a recent poster on a 4Runner forum who had a similar issue:

    "The mechanic drove my car and immediately diagnosed the issue. He told me that the feeling on the brake pedal is the brake motor. Since the neither of the previous 4Runners I've owned have the electronic brake-by-wire system that the new Toyotas have, this feeling is new and foreign to me. Basically, the brake motor powers up depending on the brake pressure being applied to the brake. Adjacent to the brake motor in the engine, is the brake actuator which is filled with an x-amount of brake fluid. When the fluid level in the actuator falls below the pre-programmed threshold in the system, the brake power powers up to refill the actuator to the programmed level.

    This explains why the "vibration" isn't felt every time--the actuator is re-filled every time you feel the motor working. But if you repeatedly step on the brake on and off, you will feel the motor power up almost every other press. Or on a long press of the brake, the motor can be felt towards the latter end of the braking because the pressure in the actuator is decreased due to a draining of the fluid and the motor needs to power up to refill.

    Apparently this is felt on all of the newer Toyotas (Priuses, Highlanders, Land Cruisers, etc.). The mechanic admitted that he won't be surprised that this will become an issue that will be brought up by the media/Toyota in the future."


    Do we buy this explaination? At this stage, I'm just more annoyed (and disappointed) then really concern the brakes are going to fail. I'll just continue to monitor the situation and bring it up again at the first service date and learn to live with it?! :annoyed:

    Thanks,
    KN
     
  5. Oct 23, 2010 at 10:31 PM
    #5
    Taco11

    Taco11 Well-Known Member

    Joined:
    Sep 11, 2010
    Member:
    #43080
    Messages:
    175
    Gender:
    Male
    First Name:
    Chris
    Seattle WA
    Not true. Vacuum is not used in this brake system. Its an electric pump that pumps brake fluid into an accumulator. That fluid is used for braking.
     
  6. Oct 24, 2010 at 1:40 PM
    #6
    Taco11

    Taco11 Well-Known Member

    Joined:
    Sep 11, 2010
    Member:
    #43080
    Messages:
    175
    Gender:
    Male
    First Name:
    Chris
    Seattle WA
    Basically what this system consists of is ABS module and brake booster/master cylinder all in one. Known as "Integral ABS" which oddly enough is rather old technology.

    I should clarify that the accumulator pressure is only used for power assist. Should you lose the boost pressure you will still have some braking. Just it will be a "hard" pedal feel.
     
  7. Oct 24, 2010 at 1:44 PM
    #7
    The1youluv2hate

    The1youluv2hate Well-Known Member

    Joined:
    Sep 14, 2010
    Member:
    #43233
    Messages:
    2,715
    Gender:
    Male
    First Name:
    Peps
    SP... CaL
    Vehicle:
    11 TRD sPort
    5100's@1.75 Horns (Andres) Satoshi TRD cat back BHLM
    my truck seems ok ....but ill check it out
     
To Top