i have a 96 silverado and the brake pedal almost goes to the floor when the brakes are applied. i have been told that it may be the booster. i could pump the pedal 1 time and have a good pedal, but today it takes 3-4 pumps to get good brakes. i don't see any fluid and the level is good. do you think it is more likely to be the booster or the master cylinder? any help, suggestion, or tips will be greatly appreciated!!!!

 

Master cylinder was a very common problem on those. Bleed off booster (engine off, pump pedal couple times) then try hitting the pedal hard & fast once. If it stops higher than normal the master cylinder is for sure the problem. Also check adjustment of rear brakes & hoses for swelling.