F350 Super Duty vs 3500 Denali vs The Ike Pulling 30k lbs

rhagfo wrote:
Looking at that dyno sheet best towing RPM is between 2,270 and 2,300 rpm, near max HP and max torque. After 2,270 the torque rating starts dropping off.

When you have a power curve to look at you can totally ignore the torque curve The power curve tells the whole story. According to that graph the Duramax makes peak HP at about 2500 rpm. If a gear change makes a 17% difference in rpm then up shifting at 2750 would drop the rpm down to about 2280. The power changes little over that rom range so the engine would always be putting maximum power to the rear wheels.