Every time when reaching the final seconds of braking (2003, 4x4 PU), no matter whether in drive or reverse, there is always a faint break pedal fade and actual brake fade; never enough to not stop the truck but always enough to get anyone’s attention. The brake fluid levels are fine (clean and full). My mechanic has also experienced this but can not locate a cause - a mystery.
By “fade” do you mean the pedal goes down? Does it “pump up”? Try doing it just sitting there. If the pedal slowly drops with your foot on it, it’s the master cylinder. It will pump up and cannot pass fluid “around” the piston fast enough, but a prolonged/sustained pressure will bleed down.
If it just starts losing stopping power, bleed the brakes.
Have the caliper pins cleaned and lubed. The rust build up is retarding the movement of the pads, that is assuming you have disc brakes…
Your are just going to have to get into the brake system and do a top notch cleaning,lubing, perhaps parts replacement job as you must admit your complaint is a bit off the beaten path.
Don’t forget to check for TSB’s, perhaps GM has something to say about this.
why is the comment…“off the beaten path”???..this was exactly the problem I experienced and cleaning the pins fixed it.
If your truck is equipped with the PITA ABS option i’d try temporarily disabling it. It might be kicking in when it should’nt. Have your mechanic pull the ABS fuse or relay & see if the problem goes away.