2001 chevy lumina make rumbling noise when I press on the brake and the brakes are stiffening up from time to time causing me to have to press harder and they and make me feel that they may not stop t

SOURCE: 98 Chevy Lumina has front

I may be a wheel bearing. Try shifting the weight of the car on the front tires by turning the wheelslightly while driving about 30 MPH. Don't turn enough to change lanes, just enough to put the load on the outside bearing. It may quiet down in one direction. The failed bearing is generally the side that you turned to in order to make the noise go away. Say the noise goes away when you steer to the right, the failed bearing is usually the right one.

You can also check for play by jacking up the car and shaking the tire. There should be no play.

SOURCE: Brake lights 1997 Chevy Lumina

i would check the bulbs first. then continue to the brake switch

SOURCE: 2001 chevy silverado anti lock brakes

You most likely have a wheel speed sensor dropping out this would make abs system think one wheel is locking up and therefore activate. this usually will happen rt before you stop at around 5mph or so.Also if you have bigger tires than factory and have not had abs programmed for this size it can aggravate it

SOURCE: 1999 Ford Windstar, Grinding Noise when brakes are pressed

Sounds like the pads are worn out and are grinding on the rotors. You will likely have to replace the pads and rotors.

SOURCE: Antilock brakes 97 Silverado rolls thru intersections

plug it back in and bleed your brakes dude.