Raer Brake Problems

[GMC Jim]

since I have owned this truck; have always had problems with the front disc brakes being applied before the rear brake shoes... .. Have inspected .. linings and adjustment OK... no wheel cylinder leakage.....

suspect the proportioning valve....However, GM Service manual states that "The function of this valve is to prevent premature rear wheel slide"...... My problem is the opposite....front brakes grab before the rear....

Any way to check this valve for proper operation.... or do I just replace the valve, bleed the brakes and hope for the best ???

[fine69]

Hey Jim. If the truck has sat for awhile sometimes they stick. Take 2 ballpeen hammers, one on each side. Use one like a dolly. Then smack the crap out of the other side. In multiple places.
If this does nothing just replace the valve.