Hauling Cargo: Practice Questions & Explanations

At least 20 percent of the gross combined weight of the vehicle and load should be carried by the steering axle for the driver to maintain proper steering control. If too little weight rests on the front axle, the tractor's front tires lose traction and the truck becomes hard to steer, especially in wind, on slick surfaces, and during braking. Federal regulations also impose maximum axle weight limits, but the 20 percent minimum on the steering axle is about handling, not about damage to the road. Proper load distribution is a fundamental cargo securement skill. A trailer loaded heavy in the rear lightens the steering axle and creates poor handling even though no axle is overloaded.

Federal regulations require that cargo securement be inspected within the first 50 miles of the trip, then again every 150 miles or every 3 hours, whichever comes first. Securement must also be re-inspected any time the driver changes duty status, takes a break, or before starting after a rest. The first 50 miles is the highest-risk window because vibrations and shifting often loosen straps and chains shortly after departure. The 150-mile / 3-hour rule catches gradual loosening on longer trips. Stopping only at fuel stops is not sufficient. The driver is legally responsible for the load even if a shipper or other party did the loading and securing.

Federal cargo securement standards specify a minimum number of tiedowns based on cargo length and weight. For an item 5 feet long or less and weighing 1,100 pounds or less, one tiedown is the minimum. For items longer than 5 feet, or weighing more than 1,100 pounds, at least two tiedowns are required regardless of weight. Two additional rules apply: the aggregate working load limit (WLL) of all tiedowns must equal at least half the cargo weight, and cargo that can roll must be chocked or otherwise prevented from rolling. These minimums are floor requirements; many loads need more tiedowns to meet the WLL requirement. The 1,100-pound and 5-foot thresholds combine — both must be met for the single-tiedown option.

Working Load Limit (WLL) is the maximum load a tiedown is designed to handle during normal use. It is typically one-third of the tiedown's breaking strength, providing a safety margin for shock loads, wear, and degradation. Federal regulations require the aggregate WLL of all tiedowns on a piece of cargo to equal at least half of the cargo's weight, plus enough WLL to handle dynamic forces during driving. Tiedowns must be marked with their WLL by the manufacturer. Using tiedowns beyond their WLL risks failure under braking, sudden maneuvers, or rough roads. Common WLL values: 1/4-inch chain Grade 70 has about 3,150 pounds WLL; 2-inch wide ratchet strap has about 3,333 pounds WLL, though these vary by manufacturer. Always read the tag.

FEDERAL WEIGHT LIMITS (23 USC 127 and 49 CFR 658): GROSS VEHICLE WEIGHT (GVW): 80,000 lbs maximum on Interstate highways.

Single axle: 20,000 lbs maximum. TANDEM AXLE (two axles within 40 inches of each other): 34,000 lbs maximum. BRIDGE FORMULA (Federal Bridge Gross Weight Formula): The weight any group of axles can carry is also limited by their axle spacing to protect bridges — the farther apart axles are, the higher the allowable weight. Even if you're under the 80,000 lb limit, you can still be overweight if axle spacing is wrong.

Practical operation: An 80,000 lb combination typically has a 12,000 lb steering axle, two drive axles at 34,000 lbs total, and a trailer axle at 34,000 lbs (total: 80,000 lbs). Overloading causes: tire failure from overheating; brake failure from excessive stopping demands; bridge and pavement damage; federal and state fines; liability for resulting accidents.

State oversize/overweight permits: Some states allow heavier loads on non-federal roads with permits (100,000-200,000+ lbs for special loads). These require route surveys, pilot vehicles, and travel restrictions.

Scale houses: All states operate weigh stations requiring CMV compliance. Bypassing an open scale is a violation. Pre-clearance programs (PrePass) allow compliant carriers to bypass on some routes.

FEDERAL CARGO SECUREMENT RULES (49 CFR Part 393.100-136) establish minimum requirements for securing cargo to prevent shifting, falling, or leaking during transport.

General rule: Cargo must be secured well enough that it can't shift or fall during normal braking, acceleration, and cornering, AND during emergency maneuvers.

Tie-down requirements: Minimum aggregate working load limit of all tie-downs must equal at least HALF THE WEIGHT of the cargo. For cargo 10 feet long or less: minimum 2 tie-downs. For cargo over 10 feet: additional tie-downs at approximately one per additional 10 feet.

Methods of securement: TIE-DOWNS — straps, chains, cables, ropes rated for the load; BLOCKING — wood or rubber blocks placed against cargo to prevent movement; BRACING — framework preventing cargo movement; FRICTION — non-slip mats between cargo and trailer floor; DUNNAGE — padding to prevent damage and reduce movement.

Cargo inspection: Inspect cargo before and after the first 50 miles and every 3 hours or 150 miles thereafter (or when stopping). Tie-downs loosen through vibration and must be re-tensioned.

Exempt cargo: Some cargo types have specific rules: flatbed with logs, metal coils, concrete pipe, auto-transport — each category has its own requirements.

Consequences: Unsecured cargo that falls and causes injury or death can result in criminal liability, loss of CDL, and massive civil judgments.

A BILL OF LADING (BOL) is one of the most important documents in freight transport.

What it is: A legal document serving three functions: (1) RECEIPT for cargo — confirms the carrier received the goods from the shipper; (2) CONTRACT for carriage — defines the terms under which the goods will be transported; (3) DOCUMENT OF TITLE — may transfer ownership of goods when properly endorsed.

What it contains: Shipper's name and address; consignee's (recipient's) name and address; description of goods (quantity, weight, packaging, class); handling instructions; declared value; freight charges; any hazardous materials information (if applicable, must reference shipping papers). DRIVER'S RESPONSIBILITY: The driver should review the BOL before loading to understand the cargo; verify count and condition of cargo against the BOL before signing; note any discrepancies ('3 pallets, 1 damaged') before signing; carry the BOL in the cab for the entire trip; surrender it to the consignee upon delivery.

Hazardous materials bills of lading: HazMat shipping papers have specific required information (proper shipping name, UN number, hazard class, quantity, emergency contact number) and must be kept in a specified location in the cab (within reach of the driver when seated, or in the door pocket on the driver's side). Never sign a BOL for a load you haven't verified.