Transporting Cargo Safely
Weight and balance
Cargo questions are really weight-and-balance questions. You must stay under the gross vehicle weight rating (GVWR), the gross combination weight rating (GCWR) if you tow, and the limit for each axle. Spread the load evenly, keep heavy freight low, and keep the center of gravity centered - a high or shifted load makes the vehicle far more likely to roll over in a turn or sudden maneuver.
Securement rules
Every load needs at least two tie-downs. For articles longer than 10 feet, use four tie-downs, plus one more for each additional 10 feet of length. The combined working load limit (WLL) of all tiedowns must be at least half the weight of the cargo. Tiedowns must be attached to the vehicle's tiedown points, not to the cargo of another article, and the front of the load must be blocked or restrained so it cannot shift forward.
Visibility
Cargo may not cover lights, reflectors, or license plates, may not obscure your view, and may not make the vehicle unsafe to handle. Anything that could fall or blow off must be secured and, where required, flagged.
Traps
The classic trap is confusing the number of tie-downs with the strength requirement, or using breaking strength where the question asks for working load limit. Another is assuming a sealed trailer frees you from responsibility - you are still responsible for the weight and for inspecting what you can.
Worked example
A 12-foot, 1,200-pound crate needs four tiedowns (over 10 feet) whose combined WLL is at least 600 pounds. Four straps rated 150 pounds each meet the rule exactly.