[RC-Monster Mike]

That truck is going to need a serious motor and some serious voltage to get 20 minute runtime and 50 mph. Are you planning on using the stock brake linkage? Also, I need some info to try to determine the best motor for this beast, such as diff ratio, transmission ratios, tires size, etc.. Then, I can possibly make a few suggestions for you. I think you will need more than the basic xl for this beast. I can get the higher end Lehner stuff, which will be a necessity(need a larger motor!) for this heavy beast of a truck. I don't know if the drivetrain will hold up to the power of a 50mph brushless setup, either.