Wheeled truck cranes can usually climb grades up to ____% grade.

• A. 30% grade
• B. 40% grade
• C. 50% grade
• D. 20% grade

Answer: (B)

Climbing a grade with a wheeled truck crane is all about staying stable and maintaining traction. When the crane moves uphill, the weight shifts toward the uphill side, which can reduce tire grip and raise the risk of tipping if the slope is too steep. Since wheeled cranes typically don’t deploy outriggers during travel, their stability and braking control rely mainly on the wheelbase, ballast, and tire traction. That combination sets a practical upper limit for safe travel on slopes. The usual maximum is about 40% grade, which means for every 100 units of horizontal distance you rise 40 units, roughly a 21.8-degree incline. Going steeper increases the chance of loss of control, reduced braking effectiveness, or rollover. So the commonly cited limit is around forty percent; lower values are safer but unnecessarily restrictive for typical operations, and higher values exceed safe traction and stability margins.