The most likely thing is the small rubber hoses on each the front brakes. They are flexible so the wheels can turn but tend to break down on the inside because of it. When they start to break down you can force fluid through them with the breke pedal but because they are starting to be blocked inside the hose it takes longer for the fluid to return because it's not under as much pressure. Therefore they hold the pressure on the brakes pads and lock them up a little. As the brake pads heat up, they lock up. That is where I would start looking. Good luck.
Slam on your brakes. If your brakes lock up, then you do not have ABS. If your brakes do not lock up and you hear a knocking type of noise from your brakes, then you have ABS.
there are bleeders on the wheel cylinders
does you truck have drum brakes in the back
Do you have anti lock brakes that might be it if not your rotors maybe warped
Most likely brake master cylinder.
Be pointless. The point of anti-lock brakes it to effectively "pump" the brakes for you.
Most likely you do not have anti-lock brakes in your vehicle. Other possible answer is that your anti-lock brakes are malfunctioning. If you have anti-lock brakes you should see a mechanic as soon as possible.
Wheel cylinder (drum brakes) or caliber (disc brakes) sticking. If you find this to be the case you need to replace both sides and replace your brake fluid which is contaminated with moisture.
Bad fluid in master cylinder,flush system,bleed brakes
May be the proportioning valve by the master cylinder
Be sure to change both front brake hoses. I didn't and my calipers would lock up.
Yes it is.