A wheel tractor is operating in it is fourth gear range with full rated revolution per minute. Tractors speed is 7.00 miles per hour. Ambien air temperature is 60 Fahrenheit, and operating attitude is sea level. This tractor is towing a fill material loaded pneumatic trailer while climbing with 5 % slop. Rolling resistance is 55lb/ton. Tractor is single axle and it is operating weight is 74,946 lb. The loaded trailer weighs 55,000 lb. The weight distribution is for the combined tractor- trailer unit is 53% to the drive axle and 47% to the rear axle.
The manufacturer, for the environmental conditions as given above, rates the tractive effort of the new tractor at 330 rimpull HP. What percentage of this manufacturers rated rimpul HP actually develop?