This was a pulley question that was presented to me today at work. They are using two pulleys, one is driven by a gearbox, the other is sort of an idler, between the two pulleys there is a total of 6 wraps. They are trying to pull a 8000lb cart up and down a straight incline of 5 degrees over 30 feet. The cart is rolling on steel rails. I am lost on how to calculate the torque needed to pull this cart up their little incline. Thanks to those who can guide me in the right direction.