i am pretty sure you have a bendix system, which is crap.
i dont know anything about your jeep, if anythings been replaced etc etc, but it sounds like its your MC. if thats the case there was a recall on the bendix system that i had done on my 91. but yours may not be able to be done. i have no idea youll have to check and see yourself.
here is the info on the recall though.
The recall was only for 10years but it is lifetime on the pump and/or piston assy. You may have to call Chrysler's 800 number and tell them you need a copy of Recall Notice 702, Good Luck
NHTSA Campaign ID Number: 96V260000 - Hide Details
Recall Data: 12/27/1996
Components: SERVICE BRAKES, HYDRAULIC:ANTILOCK
Units Affected: 52000
1991 JEEP CHEROKEE SERVICE BRAKES, HYDRAULIC:ANTILOCK
Recall Date: 12/27/1996
Summary:
VEHICLE DESCRIPTION: VEHICLES EQUIPPED WITH ANTILOCK BRAKE SYSTEM (ABS). THE ANTILOCK BRAKE SYSTEM (ABS) HYDRAULIC CONTROL UNIT CAN EXPERIENCE EXCESSIVE BRAKE ACTUATOR PISTON SEAL WEAR WHICH COULD CAUSE PUMP-MOTOR DETERIORATION.
Consequence:
IF THIS OCCURS, THE ABS FUNCTION WOULD BE LOSE AND REDUCED POWER ASSIST WOULD BE EXPERIENCED DURING VEHICLE BRAKING. THE INSTRUMENT PANEL WARNING LIGHTS WILL SIGNAL SYSTEM IMPAIRMENT AND THE BASE MANUAL BRAKES WILL REMAIN FUNCTIONAL.
Remedy:
DEALERS WILL TEST THE VEHICLE'S ABS AND REPAIR AS NECESSARY. THE WARRANTY ON ALL ABS COMPONENTS WILL BE EXTENDED TO 10 YEARS OR 100,000 MILES (EXCEPT FOR THE BRAKE ACTUATOR PISTON ASSEMBLY AND THE PUMP-MOTOR ASSEMBLY WHICH WILL HAVE A LIFETIME COVERAGE). OWNERS WILL BE REIMBURSED FOR PREVIOUS ABS COMPONENT REPAIR COSTS.
