Brake issue on 2004 dodge ram 2500

[Jeff72]

I am haveing brake issues on a 2004 ram 2500 the brakes are very touchy and has no travel in the pedal before the rear brakes start to take hold and will lock up easy in gravel. i have replaced the master cylinder, hydroboost (used) and rear lines going to calipers and has made no change just wondering if could be in the ans controller or where else to look. It makes it hard to pull a trailer as touchy as the brakes are the dealer i took it too could not figure it out said they thought it was master cylinder. Open for ideas. I have cracked brake lines and none seem to be holding pressure on them.It is a 2004.5 dodge ram 2500 6spd quad cab.

 

[p-Bar]

Does it lock up on pavement?

 

[TWebster]

Something I found in my 2005 fsm, maybe it will help
HYDRAULIC/MECHANICAL
DESCRIPTION - ELECTRONIC VARIABLE BRAKE PROPORTIONING
Vehicles equipped with ABS use electronic variable brake proportioning (EVBP) to balance front-to-rear braking. The
EVBP is used in place of a rear proportioning valve. The EVBP system uses the ABS system to control the slip of
the rear wheels in partial braking range. The braking force of the rear wheels is controlled electronically by using the
inlet and outlet valves located in the integrated control unit (ICU).
OPERATION - ELECTRONIC VARIABLE BRAKE PROPORTIONING
EVBP is able to decrease, hold and increase rear brake pressure without activating full ABS control. Upon entry into
EVBP the inlet valve for the rear brake circuit is switched on so that the fluid supply from the master cylinder is shut
off. In order to decrease the rear brake pressure, the outlet valve for the rear brake circuit is pulsed. This allows
fluid to enter the low pressure accumulator (LPA) in the hydraulic control unit (HCU) resulting in a drop in fluid
pressure to the rear brakes. In order to increase the rear brake pressure, the outlet valve is switched off and the
inlet valve is pulsed. This increases the pressure to the rear brakes.
The EVBP will remain functional during many ABS fault modes. If both the red BRAKE and amber ABS warning
indicators are illuminated, the EVBP may not be functioning.

 

[p-Bar]

That's why I'm curious if it locks up on the asphalt. You may have found the cause.