i have a break problem with a 92 7.3 4x4 it will stop just not enough to stop on a dime or a cattle trailer loaded up its kinda scarry. like the pedal feathers to the floorboard but it just doesn't stop right i replaced the booster mastercylinder and the vac pump. the rabs light comes on after driving about ten miles and the truck stops just when you push harder than normal on the pedal. i need help with this so i can get back to work hauling back and forth oklahoma and for the local ranchers.

 

How is the rest of the brake system? Front calipers, pads, rotors and brake hoses on good shape? Rear lines and hose too?

Did you bench bleed the new m/c before you installed it?

 

Hard to give you a definate answer but if I had to guess I would say that you have air in the system. The pedal should go no where near the floor.
Assuming you bench bled the master cyl then you need to bleed in this sequence, right rear, left rear, RABS module, right front, left front until all air is out.

 

ok thank you for the help but i am kinda of new to this but is the module located behind the tires and looks kinda like a grease zert that u turn to shoot break fluid? and how do you bench bleed the master cylinder i have bled the breaks time and time agian but it got me no where. the rotors and pads are good. i kinda need a location and the RABS module.

 

The RABS module is bolted to the inside of the left side frame rail about level with the drivers feet. There is a bleed screw on it, so you just bleed it like a wheel cylinder.
Bench bleeding is where you screw in two adapters to the ports on the master cyl., attach clear plastic pipes to them, direct the pipes into the resevoir and then slowly pump the master cyl until no more air bubbles appear in the pipes. This is usually done with the cyl, clamped level in a vise.
However try bleeding the RABS module and see if that improves things.

 

thanks i will try that as soon as i get home

 

thanks alot guys that helped me tremendously i realy apprieciate this