having troubles with my brakes any help

K i got a 89 cherokee 4 door 4.0L auto well the brakes on front and rear have all fully been replaced including hardware we did all the brake bleeding and all that to front to rear made sure it had all the air out well now when i push on the brakes the barely work and then the pedal pauses and if you push harder it completly locks up the rear tires ONLY then once you let off the pedal the tires roll like normal well on my way home the other night it did it again this time i caught in the corner of my eye that the brake light for the emergency brake came on i thought that was weird since the emergency brake wasnt even touched if anyone has any idea what it could be it would help alot thanx

When you replaced the brakes did you replace the calipers and rear cylinders as well? When you bled them did you do it the old fashioned way with a buddy pumping the pedal or with a handheld vacuum bleeder? It sounds like what you're describing is the pedal goes almost all the way to the floor and then you press it harder and that's when the light comes on. The same thing happened to me when I replaced the calipers and tried using the vacuum bleeder on my 93 but when I did it old fashioned way all pedal pressure was back and stopping power was back.

If you dont bleed the brakes properly the vavle in the proportioning valve move(trip) causing what you describe.

The brakes grabbing like that sounds like mine worked when the rear brakes were out of adjustment. Did you adjust the brakes up with a screwdriver (going through the backing plate from underneath) after everything was assembled?

well we would bleed one tire pumping it with one person another bleeding we did it to one tire 3 times then went to the next then the next but we went around the whole jeep to every tire about 4 to 5 different sets so we fiqured that would be enough cuz no more air came out of them but ill go around and bleed them all again and see if it helps any

Pass rear/drivers rear/pass front/drivers front--in that order.

Make sure that the calipers are on the correct side (bleeder valve on top). I replaced my calipers a while back and had them on the wrong tires and it did pretty much what your describing. Also the handbrake indicator light doubles as a problem light for the brake system. Yooou can check it the same way as the check engine light if you can find the codes.

Or check to make sure your flexible brake lines aren't swelling when you press the pedal

vigman said:

Also the handbrake indicator light doubles as a problem light for the brake system. You can check it the same way as the check engine light if you can find the codes.

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89 cherokee 4 door 4.0L auto -- Renix won't even have "check engine" codes stored, much less brake trouble codes.

Shorty said:

89 cherokee 4 door 4.0L auto -- Renix won't even have "check engine" codes stored, much less brake trouble codes.

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Gotcha still kindof new to the Renix world

RCP Phx said:

If you dont bleed the brakes properly the vavle in the proportioning valve move(trip) causing what you describe.

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so how do you check the proportioning valve i'm having the same trouble with mine, a 90 xj. with all new hardware. new calipers installed correctly ( but they was not when i got the jeep). all new brake lines. new wheel cylinders, new pads and shoes, new adjusters and the back brakes are adjusted. sorry for the high jack. just trying to get it safe before my family rides in it.

joe_peters said:

Pass rear/drivers rear/pass front/drivers front--in that order.

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what happens if you don't bled it in this order, or what is the benefit?

Wel, it is the farthest from the brake MC, and if there is no air the the lines farthest, less likely to have air in the others.

does your 89 have the antilock system? its extremely common for these units to fail and in many ways. there was even a nation wide recall on them for the lifetime of the vehicle. there were many differant symptoms when they failed and the worst one was that the actuator or whatever it was called will actually lock the system open. meaning you will have NO brakes, or atleast very very little. you have to basically put all your strength into the pedal to even slow it down some. cure? replace the master with a 96 year booster and master cylinder and delete ALL the antilock system. even with the dealer installed replacement, it will fail. not worth the risk at all because it can fail at any time and you will have no braking power. im not saying this is your problem, but it was a common problem with that year with the antilock brake system. if you have it, junk it, and replace it. youll be much safer.

joe_peters said:

Pass rear/drivers rear/pass front/drivers front--in that order.

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I always thought you bleed the shortest path then progress to the longest last, in other words the reverse of what you posted. Been doing it that way for 35 years. I have been doing it backwards for 35 years, or is yours backwards?

I am having my own problems with bleeding my 87 today.