17. Do not attack a snow bank or a furrow of snow at plowing speeds.
Always reduce ground speed when applying a load to the plow. Start from a
stopped position and slowly increase speed to effectively move the snow.
18. Adjust plowing speeds to existing road conditions--the more severe
the road surface, the slower the plowing speed must be.
19. Never alter or defeat factory adjustments or materials on any safety
device, such as the trip spring adjustment, shear bolt size, or the cushion valve