hi crew,can anyone shed some light on proper function of the brake proportioning valve.have replaced everything but this on car.braking is not satisfactory,and last outing,warning lite came on...ordered new one but would like to know exactly what this does...jc

 

Well, I am no expert, but I believe the valve is responsible for shifting percentage of pressure between front and back brakes, so you can adjust how much of brake effort is applied to each area. For example, if you find that under moderate braking, your back wheels tend to lock up, you've got too much pressure to the back brakes and not enough to the front. I hope this helps you somewhat, but I am sure one of our techs will come in and provide more detailed info for you.

 

With four wheel disc brakes, the application of braking power is fairly equal, front to rear. You should have a metering block on your car. The term proportioning valve is often misused. The metering block has a preset, non adjustable flow rate for the vehicle application. A proportioning valve is an adjustable device that allows you to custom tune your brake bias. If you are replacing your brake system, there is nothing wrong with adding an aftermarket proportioning valve somewhere between along the line from the metering block and the left rear t-block. Then, you can custom tune your rear brakes. Good Luck.

 

JC, have you checked the rotors (new or not worped).Wheel bearings front and rear (proper run out) Pads new? Master cylinder? Do you have power brakes? Do you have to use both feet on the brake peddle to stop, could be the booster. Good luck, hope this helps, Petes74ttop.

 

Too much pedal with not enough stopping power usually means air in the brake lines. You might have already fixed your original problem with all the work that you've done, but left some air in the lines when you bled them after the work. Try giving them a good bleed, it is cheap and relatively easy, and might just save you alot of "swap out troubleshooting" cost.

http://www.speedbleeder.com/
http://www.amazon.com/gp/product/B0002JMIY0

And many similar products at your favorite parts store make this a breeze.

bill.