new rear brakes very tight

Truck is a 2003 put new rotors  and pads  and when I put the lower caliper bolt in its forcing the rotor tight to outside pad and it's causing the rotor to not sit flat against  the hub so when I put the lug nuts on it tweaks the rotor  to the outside pad and in turn acts like the brakes are on.  my buddy who works at a dealer never heard of it, he think it might be the wrong size rotor or offset. the rotor is 13"  and 1.187 thick give or take,  ok stupid question  do the rear calipers have slides, because I don't get how it works it has a 1" long bolt the bolts to the bracket.

surfaces were clean, new hardware,  no didn't buy new pins. so the pins are in the mounting bracket?  mine had just a 1" 12mm bolt that hold the caliper  to the mounting  bracket and yes I have done these a few times. never had a problem

YOu know they have 2 types of rotors for rear on 2002-2006 1500 trucks.
Do you have the right one?

All based on having the g80 locker or not which gives you double piston caliper versus stock which is single piston caliper....

Compare your new rotor to old one is step one.

it's has the 2 piston calipers  and the rotors  match up unless there is a different  offset. if I'm not mistaken  it's the thickness  that is different.  I'll have to try to get the pins out or just replace  the calipers.

Well if you say you have the correct ones then you need to ensure caliper pistons squeezed in all the way before installing new pads...

I use old pad and C-Clamp for this to ensure pad bottoms out on caliper..

The slide pins are actually normally included with the bracket. The slide pins are what allow your caliper to move around and pinch both sides of the pads to the rotor. Without them working you pinch one side against the rotor and it stays there prematurely wearing one pad out and heating up the end of the axle.

The slide pins need to be cleaned and greased any time you have the brakes apart. If they are rusted then you need to clean them up to make them smooth again or replace them. If they do not slide at all then you need a new bracket and new pins. Also need to inspect the boot to insure it is not torn. Replace boots if torn.

There is specialized slide pin grease. Only use that type of grease. While other stuff might work it is best to use the stuff made for it. It is cheap enough to just buy a tube every time you do a brake job. Front brakes are same setup as rear assuming 4 wheel disc brakes.

Rodney