My 2015 Chevy 3500 at work has a tool bed on it and weighs about 9,000 pounds with it. I had a mini-excavator on my flatbed trailer (about 11,000 pounds) behind me going up Afton Mountain one day. With the gas pedal flat on the floor it would only do about 35 MPH. It got me up the mountain with no problem, just a bit slow.