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Thread: Brake problem

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  1. #1
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    Brake problem

    Hey all,
    Changed my front brakes a week back but since then not feeling its a 100%.

    If you push the brakes hard or resume braking, the brake pedal goes down.

    So tried testing and floored it and it slows down pretty quick but not quick enough so that the abs kicks in.

    I checked the brake fluid and it's topped out. Checked for air and all came back good.

    Pads are in place, no noises or anything that would make you feel anything is wrong.

    Ideas?

  2. #2
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    no where u need to know
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    Bleed them.

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    Quote Originally Posted by silvernclean View Post
    Bleed them.
    I did all 4 :s

  4. #4
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    I think I remember that you also have to exercise the ABS system on sand or gravel, THEN bleed them. Otherwise it could be a deteriorating rubber brake line that's bulging and absorbing some pressure, or a leaking vacuum booster.
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    To bleed the ABS system, you need either a Tech2 or equivalent to cycle the ABS through each internal cylinder. They do this while using a power flusher. If your truck has a lot of mileage, it would be worth it to get it done to get fresh fluid throughout and eliminate this as a possible issue.

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    Hmmm... Exercise the ABS that's interesting. Funny u mention that because on other surfaces it grabs just fine. I'll attempt this again over the weekend since Its gonna be a lengthy process.

    The second scenario where I need a tech II tool man that sounds like I'm gonna need to make a visit to a mechanic to do that for me.

    It just doesn't make any sense how I'm losing pressure. All was ok before changing the brakes. Also checked for leaks nothing there. Will attempt at it and let you know. Thanks

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    How did you bleed them? Best to use a vacuum bleeder....it pulls everything (fluid and air) through the lines and out. You can rent one at places like Advance Auto for free.
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    The other alternative is a pressure bleeder. It provides pressure at the master cylinder to force the fluid out the bleed valves. I like it better than vacuum bleeders because a vacuum bleeder could conceivably suck in air past the bleed valve threads if they are opened too far (although I am skeptical that this every happens.)

    I use the Motive Products Power Bleeder and the secret to reducing your cleanup time is to use it only to pressurize the brake fluid at the master cylinder, not to fill it with fluid itself. It works great this way but you have to de-pressurize and top up the master cylinder for each wheel because you do NOT ever want to let the master cylinder go dry. Plus, always start at the wheel farthest from the master cylinder and work towards the closest. (RR, LR, RF, LF)

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    Quote Originally Posted by Chickenhawk View Post
    The other alternative is a pressure bleeder. It provides pressure at the master cylinder to force the fluid out the bleed valves. I like it better than vacuum bleeders because a vacuum bleeder could conceivably suck in air past the bleed valve threads if they are opened too far (although I am skeptical that this every happens.)

    I use the Motive Products Power Bleeder and the secret to reducing your cleanup time is to use it only to pressurize the brake fluid at the master cylinder, not to fill it with fluid itself. It works great this way but you have to de-pressurize and top up the master cylinder for each wheel because you do NOT ever want to let the master cylinder go dry. Plus, always start at the wheel farthest from the master cylinder and work towards the closest. (RR, LR, RF, LF)
    well i can tell you one thing for sure. the sequence in which i did it wasn't that for sure lol! I didn't use any tool to bleed it out. I don't know the exact mechanical terms in english but i basically did it at a wheel basis, unscrewing something and a buddy applying the brakes. The rear no problems and started bleeding immediately. The front took some time before started bleeding.

    After doing some more reading and from what you guys have posted. I'm gonna start with Roadies suggestion. Gonna brake hard a few times on gravel and i'm hoping this will reset the ABS. if that doesn't work, i'm gonna go ahead and flush out the complete system and fill her up from scratch. Will need to find a pressure bleeder though! hard to find this stuff here.

    Thank again guys i'll do the gravel thing tomorrow and post if there's any results. If not the full flushing will be on the weekend! adios for now!

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    Quote Originally Posted by fadyasha View Post
    .....I didn't use any tool to bleed it out......The front took some time before started bleeding.

    Will need to find a pressure bleeder though! hard to find this stuff here......
    I'm concerned about what you said about it taking time before fluid came out on the front.....it shouldn't. Fluid should start coming out almost immediately......

    If you can't find the pressure type bleeder, try looking for a vacuum bleeder. It's advantage is that there is no need to de-pressurize the master cylinder after each wheel....just keep the reservoir filled before each one.
    Always remember: wherever you go, there you are!
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    It basically started bleeding after pressing the brake pedal three or four times. I'll keep that in mind if tomorrow doesn't work. Final shot at this would be getting hooked up on a tech II then take it from there.

    Just realized after reading around that the soft pedal common problem for TBs but I never faced this before

  12. #12
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    You probably already know this, but when you bleed the brakes start at the bleeder screw that is the furthest away from the master cylinder (r/rear), then l/rear, r/front, l/front.

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    Morning all! So braked on gravel few times this morning and the abs kicked in. Took it again for a test run on a side road. It's a bit stiffer and the abs kicks in pretty quick but the pedal does sink in more than it used to.

    At least it's improved ! I'll hope I get a chance to work on my tb over the weekend for the bleeding part. Just found out my mother in law is flying over and will be staying for two weeks lol!

  14. #14
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    My brakes are back ha! the braking on the gravel did the trick. I went out during lunch for another round and things are back to normal. Is the pedal a bit soft? Yes, but that's how the TB usually is. Point is the ABS kicks in on streets now! Thanks all for your help
    woody79 likes this.

  15. #15
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    Glad to see you got it resolved!
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