Started the 97 Tahoe and went to hit the brake and put her in gear and the pedal was real hard. I can hear what sounds like a fan under the dash and the more I press the brake in, the more the motor wants to stall. The brakes work just real stiff for the first 20 percent pedal or so then normal to the floor and the engine stumbles, the fan noise stays constant as long as my foot is on the brake. Maybe a vaccum leak? Maybe a caliper seizing? I checked the fluid and its fine. Any help is appreciated. Thanks in advance, Jim

 

Thats pretty odd that the whole truck wants to stall out like that. May be something to do with the ABS pump. My 99' suburban had the same problem with the front brakes, but the engine didnt bog down to where it wanted to stall out... it did, however, seem like it was panting a little bit when i was hard on the brake. Does it want to stall only when you put the brake on in park or is that in gear as well?

TTT for you, i'd take it to a brake place, maybe a tire barn or some sort of place like that.

 

****UPDATE****
It seems to be a leak where the brake pedal linkage goes through the firewall. Theres a rubber boot around the linkage and its the source of the sound and i can feel air coming out. Is this easy to fix? can it be done without removing the whole booster? Thanks again.

 

Check and See if its not leaking down the side of the steering gear box as well... sounds like there was once a small pin hole that has opened up a little bigger if your feeling air now. Not too sure about the removing the booster or not.. someone will chime in.

 

Looks like I get to replace the whole power brake booster. Whats the difference between a "loaded" and "unloaded" unit?

 

Sounds like the brake booster is gone to me.