Jump to content

brake issues

cmvtx

By cmvtx
in Ask A GM Technician

Recommended Posts

cmvtx New Member

cmvtx

Posted
Posted

Question for the tech. Over the weekend I replaced all four rotors, calipers and pads on my 99 silverado Z71(nbs). I bled the brakes the traditional two person way starting at the farthest wheel and ending with the front left. I went through about a quart of fluid doing it and was certain all the air was out. The pedal travels further than before this work was done. I bled again last night and got a little air out of the right rear, with not much improvement in the pedal travel. No other lines were opened other than at the calipers and there is no fluid loss anywhere. I have done brake jobs on several of my vehicles however this is the first time on one with abs. Is there a better way for me to bleed these lines successfully or do I have to keep doing it over and over until the pedal comes back to normal??? BTW it does stop fine however the pedal is about 3/4 of the way to the floor before it will. Thanks for the help

cmvtx New Member

cmvtx

Posted
  • Author
Posted

Nope, fluid level never went below 1/4" from max mark. I do notice with the vehicle off the brake it high and hard by the second pump. But if you hold the brake and start the engine it will drop.

 

Does this model just require repeated bleeding to finally get it right?

bobcat5544 Enthusiast

bobcat5544

Posted
Posted

it is normal operation for the brakes to get hard with engine off, and then drop like that when you start the engine.

 

some time it is nessasary to bleed the system a few times.

doing a vacuum bleed is better than pumping the brakes method

alvocado Enthusiast

alvocado

Posted
Posted

I've heard of this happening when air gets into the fluid in the ABS system. If that's the case, you need to activate the ABS to bleed the fluid out and this can be done via computer at the dealer.

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.

  • Forum Statistics

    250.6k
    Total Topics
    2.7m
    Total Posts

  • Member Statistics

    343,007
    Total Members
    8,960
    Most Online
    Brendan C
    Newest Member
    Brendan C
    Joined

  • Who's Online   2 Members, 0 Anonymous, 1,070 Guests (See full list)

  • Latest Articles

  • Posts

    • Grumpy Bear
      Joke Thread

      By Grumpy Bear · Posted

    • Grumpy Bear
      The Peckish Synapse

      By Grumpy Bear · Posted

      You're better read than that Atlas. 😏   British science fiction writer Arthur C. Clarke formulated three adages that are known as Clarke's three laws, of which the third law – that "any sufficiently advanced technology is indistinguishable from magic" – is the best known and most widely cited.   Stribeck and the pivotable Hersey Number isn't voodoo nor snake oil. That part is physics. It's what marketing and bean counters do with it that is snake oil and voodoo.    Stribeck is the relationship between Hersey and the Coefficient of Friction. Within the Hersey Equation if viscosity and viscosity is 'Dependent' on.......heat.......and.......viscosity index or the temperature to viscosity slope.    Specifically Hersey is the viscosity AT THE TEMPERATURE IN THAT LOCATION FOR THAT SLOPE.   Hydrodynamic lubrication exist when the film thickness in the location is 3X the Ra roughness of the surface. This is irrespective of the hardness of the substrate. To obtain that thickness X viscosity is required for Y velocity at Z load. That's a lot of moving parts. It is also impossible to maintain in an ICE but nearly possible with a turbine under constant load.    What does that mean? Error heavy and operate light. Wear is inevitable but the rate of wear and the milage obtainable are a function of prevailing conditions and HABITS. The only penalty is viscous drag and at fractions so low as to be well worth the effort. Double the life, half the manufacturing carbon foot print. Greed is the only impediment.    The materials generated by SwRI are the RESULT not an estimation or a hypothesis.    Don't delude yourself sir, EV's have as many pitfalls as ICE's. We just don't know what they are yet and it will take longer to sort as MARKETING and GREEDY CEO's have had more time to polish the turd they are selling. 
    • Grumpy Bear
      The Peckish Synapse

      By Grumpy Bear · Posted

      You can always count on greed to prey on ignorance and stupidity.    Friend bought a 2019 Ford Flex and asked me about using Valvoline R&P 5W30 in it. Told him give the miles on it and the fact it wasn't yet using oil that it was a good plan. He uses a Valvoline quick change shop for his oil service.   First they tell him that isn't the oil the OEM recommends. He told them he didn't care what the OEM thought. Then they floated the, "But it will void your warranty"    His reply was it's a 2019, there is no warranty and informed them their knowledge of the law was lacking.    Then they tell him 'But it will ruin your motor"!.    Mine to ruin he says. Finally they give in and charge him 150% the semi-syn price    Point it the brainwash is so embedded that even the service industry is drunk on their swill. The public is right behind them. Echoing the same lies on every forum and media platform. If the end goal is indeed EV then I'd say that ship is about built. 
    • CamGTP
      Gas Prices

      By CamGTP · Posted

      Diesel hit $6.00 here today at the truck stop.   Payed $2.79 for E85 today too.
    • richard wysong
      Electrical Problem - solved

      By richard wysong · Posted

      Thanks for posting, I'm sure it will help someone

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...