The truck is a 1988 R30 Silverado dually four door weighing in at over 6600 lbs. The horsepower will be 375 hp, 400 lbs. torque with a Turbo 400 3 speed. Towing a 30 ft Airstream at 7800 lbs. Would li...
Honestly you likely will not notice much difference. Either in pulling power or fuel economy. Another question, will or could you ever recover the cost of the gear change in increased fuel economy?