Cargo Securement and Weight Distribution
This domain tests the federal cargo securement rules and weight distribution. Minnesota's exam asks about tiedown strength, number of tiedowns, axle limits, and load placement.
Securement rules
Under 49 CFR 393, cargo must be secured against forward, rearward, and lateral movement. The aggregate working load limit (WLL) of all tiedowns must be at least half the cargo weight. Use at least one tiedown for cargo 5 feet or shorter and 1,100 pounds or less; two for longer or heavier cargo; more for long articles.
Weight distribution
Never exceed the GVWR, any GAWR, or tire ratings. Minnesota's gross vehicle weight limit is 80,000 pounds, with 20,000 pounds on a single axle and 34,000 on a tandem; the bridge formula may reduce these. Place heavy freight over the drive axles and keep the center of gravity low.
Inspection
Check tiedowns and load stability, and recheck within the first 50 miles and every 3 hours or 150 miles thereafter.
Worked example
A 20,000-pound load needs an aggregate WLL of at least 10,000 pounds. Four chains rated 5,000 pounds WLL provide 20,000 pounds, which meets the rule. Reasoning: the rule uses half the cargo weight, not the full weight.
Traps that cost marks
Counting the number of tiedowns without checking WLL; ignoring axle limits while staying under gross; failing to recheck after a load shift.