The 5450 trailer is a go IMO despite the naysayers. You don't need a new truck. Get a good hitch with integrated sway control and stop worrying. Don't worry about the elevation either. I have been over a half dozen 10K plus passes with the same engine as you have hauling a much heavier trailer. Sometimes I was limited to 2nd gear and 45 mph, but so what I always got to where I was going. There is so much doom and gloom on this forum on what you can or can't pull that it sometimes get nauseating. Your trailer choice is right in line with the specs of your truck.
