[cobra2end]

I step on the break peddle and get a sound like there is a vac. leak is that the booster going out.

 

[1991 Suburban]

Yep. That means you have a hole in your diaphragm. Your booster may continue to work for a while, but eventually your vacuum leak will get bad enough that you will lose your power brakes. It's an easy fix...If you have never done it before, grab a Chilton's. It will give you a step by step...

Good luck!

 

[cobra2end]

that's what I thought thanks for the info. cant be to much harder the changing one on a Honda at least now ill have room to work on it. thanks for the help