Dropped95gmc

Has anyone bypassed the ABS. Module with a proportioning valve? I'm seriously considering this due to the $1000. cost of a new ABS module. Any suggestions?

tech2

pretty sure the abs pump is not involved in proportioning. When you brake in a non wheel slip condition something is reducing pressure to the rear.


even newer pickups up to 2004 with abs had proportioning valves. Whats the specific problem?

Dropped95gmc

The pump and module are sold as a complete assembly. I've replaced everything, with the exception of the pump/module and hard brake lines, from front to rear. However, the rear brakes tend to randomly stick, as if the pump will not allow fluid to properly flow. I've done some, probably not enough yet, research and found that these pumps are similar to a transmission valve body. They are also very common to go bad. Rather than spending the money on a new one, or sending it out of state to be repaired by some place I can't physically go to, I was wanting to install a proportioning valve and bypass the pump/module altogether.

tech2

what exactly did you replace; list everything.


its possilble a proportioning valve is already present.

Dropped95gmc

Master cylinder, drums, rotors, pads, shoes, all rubber brake hoses (front and rear), wheel cylinders, springs and hardware (rear), and passenger side front caliper. The only thing that has not been replaced is one front caliper and the brake booster.

The brake lines come out of the master cylinder and straight into the pump, then to the wheels.

tech2

proportioning valves usually part of the of the m/c. post a pic of the front of the m/c and any junction block that the lines go to.

Dropped95gmc

Ok. It will be tomorrow before I can as I work nights.

Dropped95gmc

Sorry for the delay in the pics, works been crazy this week

tech2

no p-valves on that m/c

Dropped95gmc

Yea, straight from m/c to the pump, then out to the wheels.