I use it when launching, E brakes are always one of those things.....Use it or loose it. If you continue using it, they usually work consistently, stop using it, and run into problems when you actually want it.

03 Avalanche 2500 I always use the parking brake, 4 low and turn the wheel to full lock so if something were to happen, the truck would roll backwards and wedge the front tires against the ramp hopefully stopping the truck and trailer/ boat from ending up on youtube. It's lifted and has 35's on it so the tire would be the only thing that contacted the ramp if it were to theoretically happen.

I always use my parking brake and I stick a wheel chock behind the rear tire. I never want my truck in the drink!! '16 Silverado 2500 Duramax

We ALWAYS us the parking brake. In addition, we place a wheel chock behind the left rear wheel. Our crew is trained to pick up the wheel chock when the vehicle moves forward.

Well I found out why my parking brakes locked up on me. One of the shoes on the drivers side was down to the metal. The other side looked ok but thin. Both of the rotors on the inside where the shoes are had a ton of fine surface rust. I replaced the shoes but still have yest to adjust them. I was reminded how much of a pain it is to do back brakes on a dually. Had to pull the axles out and pull the hubs off to get to the parking brake shoes.