Jump to content



Photo
- - - - -

Brakes


  • Please log in to reply
10 replies to this topic

#1 Clint3240

Clint3240

    Enthusiast

  • Member
  • 14 posts

Posted 26 January 2010 - 04:22 AM

i have replaced all of my calipers and rotors and bleed the brakes a ton, but they are still very soft, any ideas? i wasn't sure how to test the master or boost. 1500 2003 silverado lt

Edited by Clint3240, 26 January 2010 - 04:22 AM.


#2 Bowler807

Bowler807

    Enthusiast

  • Member
  • 163 posts
  • Name:Mike
  • Location:Butler PA
  • Gender:Male
  • Drives:08 Sierra CC, 03 Deville DHS, 97 BMW vert

Posted 26 January 2010 - 05:19 AM

What kind of braake pads do you have on it?

Some of the aftermarket pads feel like sponges.

#3 Stevens11

Stevens11

    Senior Enthusiast

  • Member
  • 8,153 posts
  • Location:Bellefonte, Pa
  • Gender:Male
  • Drives:2011 GMC Sierra Crewcab 6.2L

Posted 26 January 2010 - 08:36 AM

What kind of braake pads do you have on it?

Some of the aftermarket pads feel like sponges.


Agreed, I put some crappy pads on once, and they felt like sponges. I replaced with HD pads and everything was back to normal :) Can you give more info. Why did you change calipers AND rotors and did you change the pads too?

Edited by Stevens07, 26 January 2010 - 08:37 AM.

Posted Image

Storm Gray TRUCK CLUB: Member #1
2011 GMC Sierra SLT Crewcab 6.2L with NHT and 3.73 gears


Visit My Website


Current truck:
Denali Grill, 2" RC Leveling kit, Boss MT100 20x8.5 wheels w/ 305/50r20 Cooper Discoverer H/T Plus tires, Blackbear tuned, Extang Full Tilt Bed cover, GMC Bedrug, 15% Tint, and Custom Dynamics light bar.

Previous trucks:
2007 Sierra 6.0 Vmax crewcab 4x4, 275/55r20's Cooper Zeon LTZ tires, Corsa Sport Exhaust, Denali Grill, Bedrug, Extang Full Tilt Tonneau Cover, Blackbear performance Custom tune
2003 Silverado 5.3L extended cab 4x4, 6" Skyjacker lift, 315/75r16 BFG tires, Goodmark Cowl hood, Billet grill, K&N 77-Series intake, Magnaflow exhaust, Wait4me PCM tune
2001 S10 Crewcab 4.3L 4x4; 3" body lift, 31" BFG K/O tires, Flowmaster 50-series exhaust, K&N 63-series intake, relocated IAT sensor, E-fans, TB Spacer, Jet stage 2 chip with B&M shift improver

#4 dlewis1111

dlewis1111

    Senior Enthusiast

  • Member
  • 1,091 posts
  • Name:David
  • Location:Phenix City, AL
  • Gender:Male
  • Drives:2008 Silvefrado

Posted 26 January 2010 - 08:38 AM

i have replaced all of my calipers and rotors and bleed the brakes a ton, but they are still very soft, any ideas? i wasn't sure how to test the master or boost. 1500 2003 silverado lt


There may be a special bleed procedure for the ABS mobule that requires a programmer be hooked up in order to cycle the module to different positions to eliminate all the air. Not sure on this one, but my buddy had a similar experience.

Posted Image


#5 USMdude

USMdude

    Senior Enthusiast

  • Member
  • 1,702 posts
  • Name:Jbo
  • Location:Mississippi
  • Gender:Male
  • Drives:1999 GMC Sierra

Posted 26 January 2010 - 08:55 AM

i have replaced all of my calipers and rotors and bleed the brakes a ton, but they are still very soft, any ideas? i wasn't sure how to test the master or boost. 1500 2003 silverado lt


Why did you replace calipers?? What was the problem to start with?

Yes, their is a special procedure to bleed the ABS module. If you allowed the brake fluid to run dry back to the module it will have to be bleed.

A bad brake hose will cause spongy pedal problems as well as sticking calipers and uneven brake pad wear.

Also, what was your method to the madness of bleeding the brakes?

Jbo

edit: I use two types of brake pads ONLY. NAPA Premium Pads (AE OR CMX) OR OE. I have never created a spongy pedal with a set of brake pads (not to say its not possible but I never have). My money is on a brake hose!!

Edited by jblakeney, 26 January 2010 - 08:59 AM.


#6 Clint3240

Clint3240

    Enthusiast

  • Member
  • 14 posts

Posted 26 January 2010 - 01:50 PM

im not sure what pads im using, medium grade from napa i think, and i replaced the rotors because they were thinning out, and then the 2 of the calipers were frozen and then 1 caliper striped its threads inside. i have only done 3 now that i think of it. they way i was bleeding the brakes was push on the pedal release the air screw and tighten then release the pedal

but my brakes are really soft and its hard to stop with a boat hooked up, i have to down shift the truck to help

Edited by Clint3240, 26 January 2010 - 01:52 PM.


#7 USMdude

USMdude

    Senior Enthusiast

  • Member
  • 1,702 posts
  • Name:Jbo
  • Location:Mississippi
  • Gender:Male
  • Drives:1999 GMC Sierra

Posted 26 January 2010 - 06:55 PM

im not sure what pads im using, medium grade from napa i think, and i replaced the rotors because they were thinning out, and then the 2 of the calipers were frozen and then 1 caliper striped its threads inside. i have only done 3 now that i think of it. they way i was bleeding the brakes was push on the pedal release the air screw and tighten then release the pedal

but my brakes are really soft and its hard to stop with a boat hooked up, i have to down shift the truck to help


The front 2 calipers were stuck? Bleeding procedure is good as long as you have a hose on the bleeder screw and the other end of the hose submersed in brake fluid.

Jbo

#8 Zembonez

Zembonez

    10 YEAR GMT MEMBER

  • Truck of the Year
  • 18,072 posts
  • Name:Jim
  • Location:Republic of Texas
  • Gender:Male
  • Drives:GMC Sierra

Posted 26 January 2010 - 08:00 PM

Ceramic pads will improve the feel a bit (as long as there is no air in the system). GM trucks all have a slightly mushy pedal (but great brakes). It's a characteristic of the trucks. I'm sure you know the difference between normal and too soft since it is your truck.

a3-15-20124-07-34PM_0043acopy_zpsd6a10ce

FOUNDER of the RED TRUCK CLUB .


#9 dlewis1111

dlewis1111

    Senior Enthusiast

  • Member
  • 1,091 posts
  • Name:David
  • Location:Phenix City, AL
  • Gender:Male
  • Drives:2008 Silvefrado

Posted 26 January 2010 - 08:35 PM

Like I said earlier, you need to look into the special procedure for bleeding the system with ABS (assuming you have them) or you will never get the pedal feel back.

Posted Image


#10 rmck490

rmck490

    Enthusiast

  • Member
  • 75 posts
  • Location:Colville, WA
  • Gender:Male

Posted 26 January 2010 - 08:52 PM

Like I said earlier, you need to look into the special procedure for bleeding the system with ABS (assuming you have them) or you will never get the pedal feel back.


I agree. The ABS needs to be bled correctly to function right. Below is the procedure for a 2000 Silverado which is probably similar to yours. You'll notice it uses a scan tool as part of the procedure. That would be a Tech 2 or maybe a Snap On scan tool.

Important:


  • Use the two-person bleed procedure under the following conditions:
  • Installing a new Electro-Hydraulic Control Unit (EHCU) or new Brake Pressure Modulator Valve (BPMV) .
  • Air is trapped in the valve body
  • Do not drive the vehicle until the brake pedal feels firm.
  • Do not reuse brake fluid that is used during bleeding.
  • Use the vacuum, the pressure and the gravity bleeding procedures only for base brake bleeding.
Two Person Procedure



  • Raise the vehicle in order to access the system bleed screws.
  • Bleed the system at the right rear wheel first.
  • Install a clear hose on the bleed screw.
  • Immerse the opposite end of the hose into a container partially filled with clean DOT 3 brake fluid.
  • Open the bleed screw 1/2 to one full turn.
  • Slowly depress the brake pedal. While the pedal is depressed to its full extent, tighten the bleed screw.
  • Release the brake pedal and wait 10 - 15 seconds for the master cylinder pistons to return to the home position.
  • Repeat the previous steps for the remaining wheels. The brake fluid which is present at each bleed screw, should be clean and free of air.
  • This procedure may use more than a pint of fluid per wheel. Check the master cylinder fluid level every four to six strokes of the brake pedal in order to avoid running the system dry.
  • Press the brake pedal firmly and run the Scan Tool Automated Bleed procedure (all except diesels above 15,000 GVW) once, or run the Function Test (diesels above 15,000 GVW) four times. Release the brake pedal between each test.
  • Bleed all four wheels again using Steps 3 - 9. This will remove the remaining air from the brake system.
  • Evaluate the feel of the brake pedal before attempting to drive the vehicle.
  • Bleed the system as many times as necessary in order to obtain the appropriate feel of the pedal.


#11 USMdude

USMdude

    Senior Enthusiast

  • Member
  • 1,702 posts
  • Name:Jbo
  • Location:Mississippi
  • Gender:Male
  • Drives:1999 GMC Sierra

Posted 27 January 2010 - 01:20 AM

Like I said earlier, you need to look into the special procedure for bleeding the system with ABS (assuming you have them) or you will never get the pedal feel back.


I agree. The ABS needs to be bled correctly to function right. Below is the procedure for a 2000 Silverado which is probably similar to yours. You'll notice it uses a scan tool as part of the procedure. That would be a Tech 2 or maybe a Snap On scan tool.

Important:


  • Use the two-person bleed procedure under the following conditions:
  • Installing a new Electro-Hydraulic Control Unit (EHCU) or new Brake Pressure Modulator Valve (BPMV) .
  • Air is trapped in the valve body
  • Do not drive the vehicle until the brake pedal feels firm.
  • Do not reuse brake fluid that is used during bleeding.
  • Use the vacuum, the pressure and the gravity bleeding procedures only for base brake bleeding.
Two Person Procedure



  • Raise the vehicle in order to access the system bleed screws.
  • Bleed the system at the right rear wheel first.
  • Install a clear hose on the bleed screw.
  • Immerse the opposite end of the hose into a container partially filled with clean DOT 3 brake fluid.
  • Open the bleed screw 1/2 to one full turn.
  • Slowly depress the brake pedal. While the pedal is depressed to its full extent, tighten the bleed screw.
  • Release the brake pedal and wait 10 - 15 seconds for the master cylinder pistons to return to the home position.
  • Repeat the previous steps for the remaining wheels. The brake fluid which is present at each bleed screw, should be clean and free of air.
  • This procedure may use more than a pint of fluid per wheel. Check the master cylinder fluid level every four to six strokes of the brake pedal in order to avoid running the system dry.
  • Press the brake pedal firmly and run the Scan Tool Automated Bleed procedure (all except diesels above 15,000 GVW) once, or run the Function Test (diesels above 15,000 GVW) four times. Release the brake pedal between each test.
  • Bleed all four wheels again using Steps 3 - 9. This will remove the remaining air from the brake system.
  • Evaluate the feel of the brake pedal before attempting to drive the vehicle.
  • Bleed the system as many times as necessary in order to obtain the appropriate feel of the pedal.


Kudos this is a good rendition of the proper brake bleed, but allow me to add: Right Rear, Left Rear, Right Front, Left Front as an order for the bleed sequence (that will get you bleeding the longest line to the shortest line). The Genisys scan tool will do this as well as the Pegisys. The scan tool bleed of the brake module should not be required for a caliper change. Just a 4 corner bleed. However, I could see having to bleed it if you have sucked air around in the system by an improper bleed procedure being done.

Just an after thought. The brake bleeder screw on each caliper is the at HIGHEST POINT right?????? Not pointing down....... They should all point up^.. ON every wheel. I have seen this happen a couple times... Customer walks in my store I sell person A 2 calipers. Later person A come back complaining of spongy pedal only to discover when I go to look L and R have been reversed on installation.

By the way the Blue Box at NAPA is the Safety Stop Pads (Middle Grade pads) they are Ceramics for this application. These are very quite pads and have a good service life too boot.

Jbo




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users