'93 GC Front Brake Problem

I've noticed that my brakes have been acting up on me recently. When I try to stop at speeds over 35 MPH my parking brake light on the gauge cluster turns on and I loose my front brakes. If I push too hard my rear tires lock up. The light stays on until I brake again at speeds under 35. When I brake this time, I feel a click in the pedal and I regain my front brakes. I took the brakes apart and noticed the right rear drums auto adjuster cable had broken and replaced that. The front disk brakes were repadded and re-rotored 6 months ago. There is plenty of meat left on the both the front and rear pads. The parking break still works like stock. However, after I fixed the cable, the problem seems to be happening even more. There is fluid and the master and there are no leaks. Any help would be greatly appreciated.

Reply to
Adam
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That is either air in the system or a dead master cylinder or a dead combination valve. The combination valve controls the front rear pressure split. It is unusual for them to break, but anything can happen.

The MC has 'rubber' pistons and rings in it. If one gets torn or worn bad it can act something like that. It can miss the pump for half the system and catch up after a second or 3 pump.

The red light is the 'brake failure' light, not just the parking brake light.

If you have ABS, all bets are off on the above except the light. I don't know their failures.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Adam wrote:

Reply to
Mike Romain

Reply to
L.W.(ßill) Hughes III

Unfortunately the front brakes are ABS. How can I tell if the master cylinder is the problem? Is there a way of testing it?

Reply to
Adam

On the TJ you can pull two fuses to disable the ABS system.

This works well for off roading and gives the TJ half a chance against those 'Jeep eating' trees.

I don't know if that changes the symptoms or not.

Mike

Adam wrote:

Reply to
Mike Romain

Mike, I know of two relays inside the Power Distribution Center on the passenger-side in the engine compartment that can be pulled to disable the TJ's ABS as I did when I swapped in my Dana 44, but I don't think there are any fuses specifically for the ABS system. At least I never found them when I was looking for how to disable the ABS.

Jerry

Mike Roma> On the TJ you can pull two fuses to disable the ABS system.

Reply to
Jerry Bransford

You are very likely right about two relays instead of fuses. My old beast has regular brakes.

Mike

Jerry Bransford wrote:

Reply to
Mike Romain

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