IMPERIAL
The grade resistance of a vehicle is .01 times the gross weight times the percentage grade.
GR= .01 x GVW x % grade
Where:
GR = Grade resistance
GVW = Gross vehicle weight
Example:
What is the grade resistance of a vehicle having a gross weight of 10,000 lbs. on a 5% grade?
GR = .01 x 10,000 x 5 = 500 lbs
METRIC
The grade resistance of a vehicle is .0981 times the gross weight times the percentage grade.
GR= .0981 x GVW x % grade
Where:
GR = Grade resistance in newtons
GVW = Gross vehicle weight in kilograms
Example:
What is the grade resistance of a vehicle having a gross weight of 4,500 kg. on a 5% grade?
GR = .0981 x 4,500 x 5 = 2207.25 N