Rear brakes doing all the work, very little front braking power

[bribal]

I have a 2004 chevy silverado 1500 crew cab and after replacing the brakes and rotors on the front and rear and driving for about 6 months I have noticed very little wear on the front pads and rotors. Rear brakes are fine. No ABS light and brakes never lock up. No check engine light or error message. I have lost most of my braking power on the front. The outside of the rotors have rusted and you can see just a small part of the rotor wear the pad makes contact is clean.

I have bled the system and have had no air. I've read other threads that talk about the proportioning valve. Can that valve be adjusted, possibly clogged. Whatever is going on has affected both side front brakes. Would both calipers have failed at around the same time and start giving poor performance?

[Moppie]

I've you've lost power to the front brakes your stopping distances, in fact your ability to stop at all, will be hugely affected.
Enough for you to feel in regular driving.

If stomp hard on the brakes, enough to activate the ABS, does the truck pitch heavily forward?

[bribal]

Hi Moppie, thanks for the response. Abs never activate and truck does not pitch forward. Truck just comes to a very long slow stop. Brake pedal has plenty of resistance and does not go to the floor

[gmtech1]

When you bleed the brakes was there good flow from the bleeders? Are the ft pads able to move freely in their mounts? Pull the ft tires and inspect the caliper operation while someone applies the brakes, you should be able to see the caliper apply and release, also spin the rotor and see if the calipers will stop it when applied.

[bribal]

thanks for the respnse gmtech. i had good flow from the bleeders and when we spun the rotor and appplied the brakes the rotor did stop. able to grab the rotor, spin it, and apply the brake but rotor does not stop immeadiately. wondering if I should spend the money on a new prop valve or a whole new front braking system

[j cAT]

Originally Posted by bribal

I have a 2004 chevy silverado 1500 crew cab and after replacing the brakes and rotors on the front and rear and driving for about 6 months I have noticed very little wear on the front pads and rotors. Rear brakes are fine. No ABS light and brakes never lock up. No check engine light or error message. I have lost most of my braking power on the front. The outside of the rotors have rusted and you can see just a small part of the rotor wear the pad makes contact is clean.

I have bled the system and have had no air. I've read other threads that talk about the proportioning valve. Can that valve be adjusted, possibly clogged. Whatever is going on has affected both side front brakes. Would both calipers have failed at around the same time and start giving poor performance?

the front caliper pins could be the problem. most of the braking effort is the front brakes. if the rear brakes did work correctly and the front did indeed have low braking effort the ABS will come on all the time when hitting the brakes firmly.

you may have a bad booster. if this has a vac leak then you will have a hard pedal. check the vacuum with the vacuum guage. when you turn off the engine you should get at least one power brake application . if not this is an indication the booster maybe leaking or the hoses to it.

removal of the calipers and working the pistons in and out by hand. with the caliper removed from the vehicle this should be not too difficult..

whenever replacing worn brake pads step one open bleed screw .....then with a C clamp slowly push the piston back....

if you do not do this all the crap in the piston goes into the ABS valve unit...now your in a very expensive fix...