What would cause the brake to stick on a bit and cause some heat and smell?
just seems to be the rear driver side. have tire off and looking at it now

 

Possibly the rear caliper slides are all seized up so the caliper can't float. Pretty common on the rear disc equipped trucks.

 

Dragging calipers are a real common problem with these trucks. I've replaced both rear calipers on mine.
Guardrail

 

dam it how can you free them up. i sprayed some brake clean and wd40 around and taped stuff in there. went to town(about 4.5miles) was cool but then came home and it was hot

 

You will need to remove them to clean up the slides.

 

Replace them and problem will be fixed..

 

ah trucks only got 75k miles on it..
guess i baby it too much? lots of thickness left. but man those pads sure clamp up when you push the brake. have loosed off those two smaller bolts then you can rock it in and out a bit. but then she seems to tighten back up ??

 

Pull the slider bolts, buff them and add some grease, that way the salt from winter will not seize them up so bad, I replaced all my pads at about 70 km, the back ones had seized and worn out one side of the shoes, or be like me now and head to Arizona in Oct and come back in April, good luck

 

Had the same problem on mine last week. It seemed to be more the piston than the slide. Couldn't beat Napa's price at $150 for the pair. First Napa part I have bought in years, will see how long they last.

 

Mine were replace around 60k.. Now have 165k on truck and have not had the same problem with the replacements.. I used EGR for the calipers..
EBC for pads and rotors..

 

If cleaning the slides doesn't work you have a stuck piston and will need to replace them.

 

Mine stuck Friday night, noticed from the smell. The rubber boot on one of the pistons was a little frayed. This piston was almost impossible to push back in. The extra heat put 2 cracks in the rotor. So new caliper $54 and rotor $92 and life is good again.

 

I had my rears start to hang-up and took slides and the rubber boots out and then found rust/scale in the axle flange holes. Wire brush and a light work with a rat tail file and cleaned it out. Greased holes, slides and bolts and works good now.