05 1500 everything is stock with 105,000 miles
Ok guys need help here,
started a week ago and i will explain it just like this. driving to stop light from 60-0 or even threw town 25-0.... Ok getting to a stop light or stop sign i press brakes work like normal feel normal and no noise. now going 10,9,8,7,6,5 slowing down like normal and then all of a sudden it feels as if the brakes loosen up, loose their grip or something. the brakes still work but it seems like the truck took an extra 5 ft or so to stop or i have to press down harder on the pedal.
then as i sit at sign or light i feel the pedal pop 2-4 times and every time it does it the pedal will drop to the floor a little bit nothing major but enough to feel it dropping.
brakes where replaced 8 mths ago and this is just my to town and back truck i may have put 2,000 mile on it since they where replaced. all fluids are full no noise or signs of any leaks on the vacuum or brake line.
so what does this sound like to you guys?
thanks for the help JC

 

Have you ever bled your brakes? If not, try that first and bleed the system at all all four wheels. Since you just had your brakes replaced recently I have a feeling that the mechanics may have gotten some air in the system somewhere. No problem if the air is in the brake line, you can bleed that out. Harder problem if air is in the master cylinder. AIr in master cylinder could be caused by bleeding the brakes with low fluid in brake reservoir.
When bleeding the brakes, make sure that you don't take the pedal all the way to the floor. Put a 2x4 or similar under the pedal. There are some good one-man systems out there also.
Try bleeding first and let's see if that helps.

 

Could be a bad master cylinder. With heavy foot pressure ( initial braking) rubber cups inside master cylinder hold pressure. As pressure decreases (almost to a stop and letting slightly off brake pedal) rubber cups start leaking and more effort is required to bring truck to a halt. Pedal will move towards the floor.

To explain a little further, with high line pressure, the rubber cups are forced out against the master cylinder bore walls creating a seal. With lower line pressure, and worn rubber cups, the pressure seeps past the rubber cup and mc bore walls, allowing the brake pedal to go down, and naturally braking is decreased until the driver applies more pressure.
Try holding slight brake pressure on pedal....and see if the pedal slowly goes down towards floor.

 

I would bleed everything first and change ALL the fluid out and go from there. I have a excellent brake bleeder you can get from Autozone for a few bucks or Harbor Freight a few less. Bleed them all until clear fluid and no bubbles comes out and see what you get

 

I doubt you have air in the lines if they've never been cracked open.
I'd say flush all the fluid out by bleeding as well. Brake fluid is suppose to be changed 3x's already in your '05. I bet it's original. As you compresss the fluid, it becomes hot and then loses it's strength because it is contaminated.
It'll take about 30min to flush all old fluid out for new stuff. Use DOT4 Synthetic. It's better than Dot3 which I believe is what is recomended for these trucks??? I buy the big bottles of Valvoline. They are like $9. Whatever you do, don't use Dot5.
You could have leaking caliper seals as well. Take a peek when your under there bleeding to see if there's any wet spots. They could be leaking on your brake pads causing you to lose braking and cause pedal to be lost at the floor.

 

thanks guys i will be trying these things this week and i will update with results

 

Agreed, if a visual inspection shows nothing damaged/broken/leaking then the next step is to bleed and re-fill with fresh fluid...