I used an equation that I found but had to convert the values to metric and then back to standard.
The force is MU * Mass* Gravity, where MU is 0.5, the 3000lbs is converted to Newtons:13344.66 Newtons, gravity is 9.81
Force = 65455.6Newtons
Torque = 65455.6N * 0.2794m : the 0.2794 is the 11 inch shaft converted to meters
Torque = 18288.3Nm; 161865.2in-lbs
Am I on the right path with this? If so the current gearbox is greatly undersized.
Thanks for the help it is greatly appreciated.