I have a 2005 duramax with the ssbc brake kit and it feels like the brakes are barely sticking if you lift the truck up you can turn the tire by hand but there is resistance, doesnt feel totally free, any ideas?
Disc brakes always have a little drag on them. Thats how they keep the braking surface clean and dry. Unless they are difficult to turn by hand, dont worry.
Brake dust is prob keeping them from sliding freely. Take them apart and clean the slides and bolts. If that doesn't fix it, the caliper is probably junk.