Brake help 2004 GMC 2500HD

GMC2004HD · November 25, 2014

Hey all,

My name is Curry, and I am having an issue with my brakes that i can not figure out what it is. Ive taken it to 2 shops and they have told me "Your brake pads are fine" and "We cant find anything wrong with them". So i know it cant be something simple. My brakes work fine under normal everyday driving braking conditions, but if i need to slam on the brakes, very hard, it feels like the front left losses braking power, or it is slipping, or something. It is not the ABS kicking in but I have no idea what it is. This has already caused an accident and every shop must think im crazy because they all say my brakes are fine which they are not because this is still happening. Can anyone help?

Thanks so much,

Curry

RobertNY · November 25, 2014

Hi Curry.

I'm a new kid here, but I ran into almost the same trouble with a 2006 GMC 1500 Pro Sport

The shops kept telling me there's nothing they can find. They changed the master cylinder a couple times.

A friend gave me a simple fix. He has been a GMC mechanic for 40+ years.

To save money many shops use aftermarket parts on many things.

He told me have the dealer put a REAL GM master cylinder on it. I did. They got GM part.

Problem is gone. Brakes work like new.

This may work for you to.

Good luck.

gmtech4 · November 25, 2014

you have to road test with a shop foreman of a dealer with you driving and duplicate the concern , that is the only way ,

And don't throw parts at it as per above ^^^^^^^

00Silverado4x4 · November 25, 2014

Have you taken a look at that particular caliper while someone else pushes the brake pedal? Sounds like the caliper may be sticking or there is air in it. Either way, jack it up and check it out. It's a free and easy check and then you may have a better idea of what's going on for yourself.

sahls01gmc · November 25, 2014

What condition are your wheel bearings? Not sure it is the same symptoms as you are describing, but I had all sorts of braking problems when my wheel bearings needed to be replaced. The misalignment caused the ABS sensor to thinking that wheels were slipping, and it put the ABS on for no reason!

Like govtech4 said, take the foreman for a ride and duplicate the issue.

ujtruck · November 25, 2014

be sure your pads are Ac-Delco OEM, else those after market Chinese knock offs, you will cry like I used to be crying

8.1HD/ALLISON · November 26, 2014

If you want to get serious check the pressure of each brake caliper. Could be numerous things. Hoses, calipers, air in system , etc. Im assuming the truck veers to right when braking hard, since you say feels like left front slips. Brake hoses are a very likely culprit. Take a ride with tech.

02suburbanZ71 · November 26, 2014

Lots of good advice here^^^^

RobertNY · November 26, 2014

you have to road test with a shop foreman of a dealer with you driving and duplicate the concern , that is the only way ,

And don't throw parts at it as per above ^^^^^^^

I agree with all you said. I didn't throw parts at it. I bought the truck a year ago with 15k miles on it. The dealer was having trouble getting the brakes to work properly. Until they used a real GM master cylinder, I would not take the truck. They tried 3 aftermarket ones prior.

GMC2004HD · December 4, 2014

Thank you all for your responses, I will take yalls advice and let you know what I am able to find. Thanks again

hockeyguy09 · December 25, 2014

I'm having an issue with my truck. I started a topic already on it... I'm going to flush my brake fluid out and grease the slide pins on the calipers. As far as brake hoses, which ones should be replaced? From the front calipers up? Thanks

If you want to get serious check the pressure of each brake caliper. Could be numerous things. Hoses, calipers, air in system , etc. Im assuming the truck veers to right when braking hard, since you say feels like left front slips. Brake hoses are a very likely culprit. Take a ride with tech.