I have a 1996 dodge 3500 that is driving me nuts. When we bought it not to long ago the brake light would not go out after you disengaged the emergency brake. After more and more driving we noticed a pull to the right and the truck would not stop worth a crap. Had it checked for alignment and everything was already good. So I changed calipers and pads rotors seemed fine. Truck quit pulling to the right but the pedal will go all the way to the floor. Installed new master cylinder and brake booster. Red brake light still stays on, bled everything as book says, master cylinder, combination valve, rwal valve then lr,rr,lf,rf wheels. Book does not really say how to bleed the combination and rwal valves so I would just open the line going out to the system until clear fluid ran. Thanks for any info!

 

ahh just got done fxin the same problem on my truck... try replacing all the brake lines.. the lines going to the front brakes were leaking and on the rears wanted to work.. so it took about 100 feet to stop try doin that it should fix the problem

 

Sounds like it still has some air in the system or a bad master cylinder. I put on 3 master cylinder from oriellys before I got one that wasnt bad.

 

assuming this is an IFS 2X4 have you changed the front wheel bearings? jack the front end off the ground and see if you can wobble the wheel back and forth. here is my story,

was getting ready to go to Orlando and was going to pull a car for a buddy of mine to race, he was going to have his grease monkey at his shop change the front brakes, wheel bearings, and balljoints. well he changed everything and it did the same thing you described. pedal to the floor and the rears would lock up. changed the M/C, changed the front calipers, changed the RWABS solenoids, bled about 1 gallon of fluid out of everything. ended up he got the bearings at autozone and the outer bearing was the one that they listed but wasn't the correct bearing for the application. the bearing that was the right one was listed as the bearing race. the bearing was just small enough that packed full of grease it felt like it was ok, but once it got the weight of the engine on it the wheels would bow inward just enough to make the calipers bind and the fluid would bypass in the M/C....


just my experience with a 96 2wd.....

BTW here is how to check the lights using a jumper wire .... it will flash and let you know what the "code" is. it should be on the list and MAY lead to a resolution....

https://www.dieselbombers.com/12-val...tml#post278524

 

id say it still has air in the lines, start at the master cylinder and work ur way down , doing the bleeders on the wheels last when u get there do the front first then the rear, thats the way they taught us in college

 

We finally got it fixed, after replacing front brake lines, we also found the rwabs was not hooked up, no fuses or existing wires were found on the fuse block in the engine compartment. I do not know if the old owner put in some salvage parts or not. We had to hotwire the rwabs to finish bleeding the system. The abs light was pulled from the dash, it comes on and after the brake is pressed the brake light comes and stays on. Anyway the pedal doesn't go to the floor and I am done fooling with it for now. Thanks for your input!

 

each vehicle has it's own brake bleeding proceedure... most actually i think all brake specification books has the proceedures in them... and commonly you work your way to the wheel closest to the master cylinder... also the combination valve will commonly have a valve with a certain "pop" pressure IIRC arount 16 psi it has to be greater than atmospheric pressure or else in theory your brakes would be dragging continuously... until pressure is made in the rear brakes the fronts wont (shouldnt) apply... given the proportioning from front to rear with out this the vehicle would always have an abrupt nose dive and in a panic stop with compromised traction the vehicle would have a tendancy for the rear to try and pass the front up...provided it is a front/rear split system and not a diagonally split system. the reason i bring this valve up; is b/c PROPER bleeding proceedure requires you to manually "unseat" this valve... its a pain in the **** so most dont bother with it and typically get just fine results provided that the combination valve hasnt been replaced... also w/o unseating this valve gravity bleeding the front prior to actual pressure bleeding can be a bear to deal with... bench bleeding of the M/C is highly advised... most issues with the M/C can be detected prior to actually being put on the vehicle ontop of saving yourself ABUNCH of time durring the bleeding proceedure. this is what i was tought through high school and onto college, in no way am i saying i'm correct just stating this is how i was tought; just the same as you everyone else is spot on with the front end components, evena severly warped rotor with stuck slides will cause this but should be able to be pumped up, as with air problems...

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if the brake light comes on and stays on after the pedal is depressed the safety switch is being tripped within the combination valve, if 1/2 of the system is operating at a lower pressure than the other half, this valve will cut off pressure to that 1/2 of the system and kick the brake light... if no fluid leaks, i'd look into a thorough brake bleeding again

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then again this valve also has a tendancy to stick in a closed or partially closed position once it is tripped... it sits stationary for 90% of it's life time, once its moved, more than likely its stuck... turn the ky off; jab the brakes 3 good times or crack the bleeders open quickly to try and balance the valve again

 

Thought we had it fixed. Still very hard to get stopped and brake light stays on. Tower, I tried your bleed and jab, still no help thanks for the info. I think it may be combination valve or rwal valve but they are discontinued so I cannot just replace. The dealer also said that someone may have put a salvage fuse box under the hood as there is no wiring for the abs pump fuse or the abs light fuse. Is there anyone out there that has a 96 dodge that has rear wheel abs only that can look at there fuse box under the hood to see if the abs pump fuse location and abs warning light fuse locations are not wired and missing the fuses? I do not think the rwabs needs a seperate pump as far as I read in the service manual.Thanks!

 

they discontinued the combination valve and the rwal valve? wow... kind of a retarded aprt to discontinue. have you checked local parts stores to see if they can get ahold of it? so the pedal is still dropping to the floor? you may have a bad master cylinder... the 89 will bleed down and leave it to the rear brakes to hold the truck back. having the RWAL or RABS what ever they called it that year hooked up shouldnt effect bleeding or even pedel feel/symptoms. ABS systems are designed to work like a base brake system if any kind of fault should occur within the system. unless of course there is a bad valve and its letting the fluid bypass; even with this scenario it should only effect the rear brakes... get yourself a test light hook it to the positive side of the battery and then touch the light to the lug ontop of your proportioning valve; if it doesnt light have someone press the pedal if it lights there is still a good bit of air in your system somewhere and this is likely to be causing your low pedal. if it lights up w/o pressing the pedal the check valve is still tripped and fluid could be getting cut off to the front brakes... i believe your system is a 80/20 split... 80% front 20% rear, no fluid up front= very poor braking