Parking Brakes Sticking??

I tried searching, but couldn't find anyone that experienced the same problem (sorry if I missed it).
Anyways, I have an auto 2010 DCLB 4x4 and use my parking brake whenever I park on an incline to protect my trans. from having the truck's weight bounce off it. It started originally as whenever I disengaged the parking brakes, the truck would not move, I then hit the brake pedal hard and almost feel like something releases (can hear a noise, can't really describe). Lately, when I disengage and hit the brake pedal I have to press it hard 5-8 times and sometimes the truck will start to move (with me not on the gas pedal) and feels like the parking brakes re-engage stopping the truck. (dash parking brake indicator goes off whenever I dis-engage the park brake and does not come back on).
I have tried to spray WD-40 on the back axle where the parking brake lines run with no luck.

Any suggestions before I take it in to the mechanic??
Thanks!!

 

I don't have any suggestions but I have experienced the same problem. I used to use it to help me get up the ramp after loading the boat. it stuck and scared the shit outta me. thought the motor had hung on something!

but, I do use it every day for parking and it is fine. the difference I guess for me is that on the ramp I was feeding clutch and throttle and easing the brake in simultaneously. any other time I completely release the brake before putting the truck in motion.

 

Check your rear brakes inside the drum and see if there is any axle grease. I had a bad axle seal and my rear right drum was full of grease, it was causing my brakes to stick. I was having the same problems.