ok i know i am gonna sound dumb but i am not a brake man by far. had a close one today: van with no rear lighting stopped in front of us on a 55moh road to check his map, i stood on the brakes... rear end went to the sky & the jeep tried to make a left hand turn, then a right, then a left..etc. i pumped the pedal & was finally able to stop about 2 feet from killing this rocket scientist. i replaced both of the front calipers & discs & pads about 2 months ago & the rear has less then 4000 miles on the new brakes there.
no anti-lock. i bled the brakes after this incident & went out & road tested them same thing again. now the brake light comes & goes.
any suggestions?

I am going to go out on a limb on this one - I had a similar problem, but not in a Jeep but in a car with just hydraulic brakes, no power assist. The brakes seemed to bleed out OK, but then went weak and mushy. Turned out it was sediment in the brake fluid reservoir that had plugged up the small hole that leads into the master cylinder - so they bleed out OK, but when the piston retracts, then there is no fluid or very little that enters the cylinder...just a guess on my part. But, get 'em fixed and by an expert if you need to - don't mess with safety.
Richard <img src="/forums/images/graemlins/cheers.gif" alt="" />

update: going to drain & clean the brake system & replace the proportioning valve today. gonna blow out the brake lines & flush out everything. let you know whether i can stop after this or not LOL.

ok here we go: diconnected all of the lines & flushed them..got alot of dark crap out. flushed out the master cylinder & same got alot of crap out of it too.. installed a new proportioning valve & bled the hell out of all of the brakes & had to manually adjust the rear brakes ( since they werent working to auto adjust). have full pedal & LOTS of brake now.

Sounds like you have the problem fixed. Keep an eye on the master cylinder fluid level for the next couple of weeks.