Frame service may be minimized or eliminated by minimizing the concentration of stress in small areas of the frame.

1. Use vehicles only for those purposes for which the vehicles were designed:

•	Do not overload the vehicle.

•	Load the vehicle evenly.

•	Do not operate the vehicle on extremely rough terrain.

•	When picking a frame for a new vehicle or when reinforcing a frame, take into account the forces that will be placed on a frame from the operation of equipment, such as snow plows.

2. Follow the recommended practices when repairing a frame, mounting a body, or mounting equipment on a frame:

•	Avoid sudden changes in the section modulus.

•	Do not drill holes in the frame rail flanges.

•	Space the holes in the web section of a rail at least 13 mm (1/2 in) from each other.

•	Use existing holes whenever possible.

•	Do not cut holes with a torch.

•	Do not overheat the frame rails.

•	Avoid welding on the flanges.

•	Do not allow 4 or more holes to exist on the same vertical line of the web.

•	Place the holes made in the reinforcement to a distance of at least 2 times the material thickness from the edge of the reinforcement.