Most of the time my brakes a pure mush with not initial bite. Every once in a while they bite and have a lot more pedal feedback. Any ideas as to why this happens? I am also trying to chase what I think is a vacuum leak and am wondering if the two are related.

I am gathering parts to do a hydroboost swap so I hope that solves it.

 

What I believe you are experiencing is a result of what GM call's a dynamic rear proportioning (DRP) system that supposedly makes optimum use of braking capacity at both ends of the vehicle. A lot of people experience the same issues as what you are describing, typically the system learns a easy apply strategy and after one emergency stop situation, the brakes will feel like they work good for a little while until the system relearns and goes back to the mushy peddle. You can test this out by mashing the peddle hard sveral times before you crank the vehicle and then go for a drive, I bet it will drive fine for a while and go back to being crapy.

 

Never knew that.

 

Errrr, WOW, if this is true you just opened my eyes and relieved my worries. I was experiencing the exact same thing as PSM has been, and started a thread on it about 2 years ago. Hope this is all it is.

 

LOL yep same exact problem here. Im in the process of upgrading my brake system because of that issue. (just new rotors and pads for now) I have been reading a lot about the hydroboost system and will hopefully convert later this year.

 

I converted mine to the Z06 calipers and 15” Baer rotors with braided lines and while it stops a whole hell of a lot better and the peddle is 10 times better as well, it still feels as if it stops off the front brakes most of the time. You can definitely tell the difference when the rear brakes feel like they are doing their share of the work. On mine, if the truck is loaded the rear brakes apply perfectly, otherwise crap.

 

I learned my new thing for the day, time to turn my brain off

 

while i believe in hydro boost,i do also believe that the hydo boost brake system bleeds off,as well.
i have some issues with the pedal bleeding off.
my buddies "NEW" duramax does the same as well.

 

No ****. I have been having this same issue for aslong as i had my truck. I always notice it when i have to brake kinda hard over a bumpy road, and it seems like its not going to stop.

 

^
mushy brake pedal with 22's = very scary stops!