keeping dragging and then locking after 10 to 15 miles down the road. I 've replaced both calipers, pads. brake lines, master cylinder, brake booster, ABS modular valve and ABS control module. My rotors are still new. I even bleed the brakes (all 4 of them). what can cause these issues?

Follow the brake lines from the master cylinder the the ( can not think of the name of that part the brake lines go to ) but that is the part you need to replace.

@firebird338 are u talking about the ABS modular pump. if so I replaced that already

Check the brake pedal I went through the same shit put all sorts of money in the truck for no freaking reason countless hours in all it was was the brake pedal would not return to the top you would think something is wrong with the brake booster but I replaced it with three different ones all to get the same luck I ended up putting the spring on the pedal to pull it back to the top that solved all my problems so I say fuck the dumb shit drill a hole in the middle pedal bracket and one up on the metal underneath the dashboard and put a spring on it that will solve all your problems and you won’t have to pull your hair out of your head for the next month fucking with the truck that keeps locking the breaks up

The metal rod that your pedal is connected to drill a hole in it then drill a hole in the Metal under the dashboard and apply a spring that will pull your paddle back to the top and disengage the brake booster all the way problem-solving no more dragging breaks