Hy J_Wade, everything fails eventually, but this failure probably has nothing to do with what you have been doing. First off check the master cylinder (under cab floor) to see if there is any fluid in it. You could also scoot around on your creeper under the truck and follow the brake lines checking for wet spots. We usually suggest a complete rebuild of the brake system for everyone's safety, new or rebuilt master cylinder and wheel cylinders, flexible and hard brake lines new brake return springs, linings and brake drums turned or new, you get the idea. Get back to us with what you find on your inspection.