Rear Proportioning valve Question

[MyGQ]

Ok i am tracing down why my front brakes aren't working 100% all the time and i think it might be the rear Prop valve. I just wanted to know if this valve is manfunctioning will the brakes at the front also have problems? as i understand it the pressure is distributed from the primary circuit to both the front and rears (following how the brake lines are routed) also my rears lock up a bit too much at times.

Could this be the problem ?

[stimpy]

hay mate i have the same problem would love to no how to fix it

[roverrat]

Is the car lifted??

If so did they make a spacer to raise the proportioning valve to compensate?

[toughnut]

If you're rear brakes are locking up too soon then your adjustment on the rear is too long. The valve makes adjustment for the weight in the rear of your car. Ie if the back of the car is sitting lower then there is theoretically more pressure on your rear tyres and therefore more grip so you can apply more break to the rear.

So if you shorten the proporting adjustment then you should be able to fix this. Just make short adjustments.

This is a common problem if people have lifted or lowered the suspension and not put the correct adjustment in to compensate.

Your front breaks won't work as well because you won't be pushing as hard as you'd normally be because your rears are locking up too easy.

[tweak'e]

the usual trick for lifted vehicles is to pack up the mount on the axle the same amount as the lift. that makes the angle and amount of pull on the valve the same as stock.
however sometimes you can't do that due to brake lines, hand brake cables etc getting in the way.
i extended the valves arm instead. just have to watch the effect of leverage on the valve. the longer the arm the more travel required for the same amount of action by the valve. handy if your suspension is softer than stock. but if its hard the valve may not work soon enough.

[MyGQ]

i put the bracket on to raise the spring when i lifted it. it seems as if the unit is not workign cause sometimes my fronts work fine, but then every now and then the backs kick in too hard and lock the back up not the fronts, and i am running twins at the front so i should lock them before the backs, i am gunna go for broke and see if getting a new valve in fixes the problem