After replacing the front brake pads, calipers and the Master cylinder the brakes still drag and they are getting hot?

There's a number of things that can cause dragging brakes. When only one front wheel gets hot, a good suspect is a constricted rubber flex hose. Rust buildup can affect just one wheel, but usually the other one will act up soon after. The mounting surfaces the pads ride on must be cleared of dirt and rust buildup, and they should be lubricated with high-temperature brake grease. Most GM truck calipers ride on a pair of chrome plated bolts. If the chrome has lifted and / or there's rust spots on them, they must be replaced. Cleaning off the rust is not a permanent fix. Those bolts must also be greased.

When the dragging brakes just start doing that right after the pads have been replaced, suspect crud has settled and built up behind the pistons in the calipers. Before unbolting the calipers, you should be able to pry the pistons back in with a large flat blade screwdriver to make room for the new pads. You should never need a c-clamp to do that. If that is the only way to get the pistons retracted, they're being run over that crud, or there's a ring of dirt or rust on the piston that is sliding under the rubber square-cut seal. Either of those will cause dragging brakes from the pistons being unable to retract slightly after braking. The piston can be replaced, but professionally rebuilt calipers with a warranty are so inexpensive today that we just replace calipers instead.

A brake light switch that's out of adjustment and holding the brake pedal down a little will cause dragging brakes. When the dragging is occurring, pull up on the brake pedal with your foot to see if the brakes free up.

Once the mechanical issues have been checked, look for brake fluid that is being trapped under pressure. When the brakes are locked, stop on a slight incline and shift to neutral. Place a block about a foot downhill of one tire. Start by loosening the nuts holding the master cylinder to the power booster. Pull it forward about 1/8". If that works, check the brake light switch adjustment.

Next, loosen the soft metal line nuts at the master cylinder. Most likely that will not release the stuck brakes. If it does, a good, (bad) suspect is the brake fluid is contaminated with a petroleum product. That is a long story for another day.

Finally, if the brakes are still locked, crawl underneath and open the bleeder screws on the calipers. If doing that lets the brakes release, suspect the rubber flex hoses. The point is to open the hydraulic system in various places to see where the brake fluid is being trapped.

See how far this gets you, then let me know what you find.

You gotta have a power brake booster, otherwise you're going to need two strong men and a boy to push the brake pedal to stop such a heavy vehicle. Most use the common booster as you are likely familiar with, but many trucks use a hydro-boost system that runs on power steering fluid pressure. With that design, you'll see two power steering hoses connected to the hydraulic assembly the brake master cylinder is bolted to.

There are some anti-lock brake systems that do provide the power assist for stopping. I have that on my '93 Dodge Dynasty. Most systems, however, just do the anti-skid function, leaving the power assist to the regular vacuum booster.

There's an easy way to tell which system your truck uses without even looking under the hood. Start with the power assist reserve exhausted. Just press and release the brake pedal three or four times until the pedal gets really hard to push. For my Dynasty's system, that requires at least 44 pedal applications to relieve the power assist reserve. Now hold steady, normal pressure on the brake pedal, then start the engine. If you have a standard, vacuum assist power booster, the pedal will go down toward the floor a good inch or two without pushing harder on it. If you have hydro-boost, the pedal will drop too, but then it will push back up toward you with pretty good force.

Regardless, the story is the same. Check for the mechanical issues I described that can cause dragging brakes, then look for brake fluid trapped under pressure, holding the brakes applied. Let me know which things you try and the results.