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In my 98 Cherokee, the brake pedal nearly goes to the floor before the Jeep decides to stop. I flushed the brakes by connecting a small hose and pumping the old fluid out while making sure the reservoir didn't run dry. It seemed to have helped, but nothing seems to happen until the pedal gets halfway down. If the Jeep is off and I pump the brakes, pressure seems to build up and the brakes feel more "normal," but as soon as the Jeep turns on it goes back to being crappy. Any advice?

IJM

Two ideas: First, check to see if your rear drums are adjusted correctly. If they're too loose, you'll get a lot of pedal travel and poor braking. Second, pull the front pads and check to see if the pad material is tapered from wearing unevenly. This can happen if the caliper isn't sliding freely or if the pad backing plates aren't free to move against the surface of the knuckle. This will give you a lot of pedal travel before the pads bite against the rotor surface.

Password12345678

Sorry it's been so long, the cold came and I've lost motivation to work on my Jeep. Since it's been warm outside, I went ahead and checked the rear drums and the self-adjusters appear to be working correctly. Same story for the front discs. My dad was by me at the time and he said all 4 corners look pretty good.

I've noticed another symptom: Sometimes when I'm stopped for a little while, the brakes seem to start to slip, so I have to push to pedal down a little further or pump them. I know this is not normal and it's making me nervous. Is this the master cylinder? I keep a close eye on the brake fluid level and it has not gone down, so I know it's not leaking.

PatHenry

Did you bleed them at all 4 corners?

kody24

I would do a full bleed first, going from the farthest brake to the closest, but you may have a seal going bad inside the master cylinder.
if bleeding doesn't fix it, unbolt the master cylinder from the booster without unhooking anything else, and pull it out just enough to see if there is any fluid coming out of the rear seal. About half of the time when a master is going it will leak there. If there is fluid, replace the master cylinder. If there isn't fluid, it may be an internal o-ring. This can be diagnosed by starting the car and pushing the brakes hard, then hold them there while giving it just enough throttle in gear to try and move. If the pedal goes down and it starts moving, replace the master cylinder.

gat

I would test the booster since you have further travel at times. Pump the brake before starting the vehicle. Hold the brake all hard as you can while starting the vehicle. Share the result in pedal travel from starting the vehicle.

Password12345678

I bled the brakes about 6 months ago starting from the furthest brake.

I don't have enough time today to do anything too complicated, but since I'm on lunch break I went out and performed this test:
1. Pumped the brake at least 10 times until it was as firm as I can get it.
2. Pushed the brake down and started the Jeep. I felt the brake sink maybe an inch or 2.
3. Put it in gear. I didn't feel any sinkage there. I was able to rev it to 1500 and the Jeep didn't move. Can't rev it any higher or else I'll get in trouble for making noise.