My 99 Tahoe has an on going Brake problem. My brakes feel spongey.
I have replaced the Master Cylinder and bled the brakes several times. Now,with pressure on the pedal I hear a hiss as if air is leaking. When I lay under the dash and apply pressure to the brake pedal, I can feel air passing into the vehicle past the rubber boot the brake rod travels through ? Is this normal or do I have a leak someplace ?

I have had the same concern with my brakes since my 99 Tahoe was brand new. It feels like there is air in the system. I took the vehicle in when it had only 1,000 miles on it and the dealer reported this is a common characteristic of the brakes that Tahoe (and maybe other years?). Anyway, I now have 45,000 miles on the truck and there has been no change in the feel of teh brakes and they always stop on a dime!

Ok, I fixed the brakes. I repelaced the vac/ booster and discovered there are two different lengths of push rods that can be used in the booster. By increasing the length of the rod 1/8" I now have excellent brake feel and no excess pedal travel. Not a tough fix at all and I have checked my drums and rotors for excessive heating or heat due to a pad or drum riding too close and they are fine.

Were you able to get this ROD speratly? Or did it come with the booster...?

Ok, I fixed the brakes. I repelaced the vac/ booster and discovered there are two different lengths of push rods that can be used in the booster. By increasing the length of the rod 1/8" I now have excellent brake feel and no excess pedal travel. Not a tough fix at all and I have checked my drums and rotors for excessive heating or heat due to a pad or drum riding too close and they are fine.


I removed the rod and made a different one 1/8" longer. I'm forunate to have a machine shop at my business and it took all of 10 minutes to machine. The rod is a 3/8" steel dowel which you can purchase at any hardware store and make you own by ctting it to lentgh and grinding a rounded end on one end. My caution is that you don't make the rod too long and have a shoe or pad dragging from too much pressure on the master cyclinder.