Six Coils, 80,700 Pounds, and a Scale Ticket
You pick up a flatbed load of six steel coil bundles, each weighing 8,200 pounds, in Newark for a receiver 26 miles away in Parsippany. The bill of lading shows 49,200 pounds of cargo. Your tractor's steering axle is rated 12,000 pounds, the drive tandems 34,000, and the trailer tandems 34,000. Empty, the rig scaled 10,800 on the steering axle, 9,700 on the drives, and 11,000 on the trailer tandems. The coils are loaded in three rows of two, centered side to side, with the front bundle 4 feet behind the headboard. The trailer has no coil racks and no blocking. Each bundle has a single 5/16-inch Grade 70 chain over the top, ends hooked to the rub rails, tensioned by the yard crew. The bundles are 6 feet long. At the weigh station the ticket reads: steer 11,900; drives 34,600; trailer tandems 34,200; gross 80,700.
1. Which weight limits are exceeded, and can you fix it by sliding the trailer tandems?
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Compare each ticket reading to its limit:
| Axle | Scale | Limit | Result |
|---|---|---|---|
| Steer | 11,900 | 12,000 | 100 lb under |
| Drives | 34,600 | 34,000 | 600 lb over |
| Trailer tandems | 34,200 | 34,000 | 200 lb over |
| Gross | 80,700 | 80,000 | 700 lb over |
Sliding the tandems cannot fix this. Sliding them rearward transfers weight off the drives onto the trailer tandems - it cures the 600-lb drive overload by making the 200-lb trailer overload bigger. Sliding them forward does the reverse. Either way you are moving weight between two axles that are already over.
Here is the number that settles it: the four rear axles together carry 34,600 + 34,200 = 68,800 lb against 68,000 lb of combined rating. The group is 800 lb over no matter how you divide it. The only axle with headroom is the steering axle, and it has 100 lb - not 800.
So the fix is weight removal, not weight distribution. The smallest unit available is one 8,200-lb bundle, which also clears the 700-lb gross overload with room to spare. Reweigh before leaving the scale; do not drive off assuming the math worked.
2. Are the six chains enough to secure 49,200 pounds of steel coils? Show both tests.
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Securement has to pass two separate tests, and this load passes one and fails the other.
Test 1 - aggregate working load limit. Cargo not requiring special handling must be secured to at least 50% of its weight: 0.50 × 49,200 = 24,600 lb of aggregate WLL. A 5/16-inch Grade 70 chain is rated around 4,700 lb, so six chains give 28,200 lb. This test passes.
Test 2 - number of tiedowns. Articles 5 to 10 feet long require two tiedowns each. The bundles are 6 feet, so 6 × 2 = 12 tiedowns required. You have 6. This test fails, and it is the one that decides the load.
The problem the arithmetic misses. Steel coils are round. A chain laid over the crown of a smooth coil is a chain that can walk off in a hard stop or a swerve - and a 8,200-lb coil leaving the deck at 55 mph does not care how good your WLL total was. Coils need to be blocked, cradled in coil racks, or secured under the coil-specific provisions of the cargo rules. Hooking to a rub rail is also questionable: on many flatbeds the rub rail is not a rated attachment point.
Verdict: the load is under-secured. Either it gets racks or blocking plus paired tiedowns, or it does not move.
3. What do you actually do now, standing on the scale with a ticket in your hand?
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- Stop and document. Keep the scale ticket, photograph the load and the chain configuration, and note the time. The ticket is the proof that you were overloaded at pickup, not at the receiver.
- Tell dispatch and the shipper, with numbers. "Gross 80,700 against 80,000; drives 600 over; trailer tandems 200 over; six tiedowns against twelve required." Numbers end arguments that adjectives start.
- Take one bundle off. That clears all three weight problems. Have it done at the yard or at the scale, not on the shoulder.
- Re-secure the remaining five properly - racks or blocking, paired tiedowns meeting the 5-to-10-foot rule, front bundle against the headboard.
- Reweigh and confirm every reading before you roll. Do not assume the removal fixed the distribution; taking a bundle off the middle row changes the loading on both tandems.
- Re-check chain tension after the first 25–50 miles. New chains and new contact points settle, and a slack chain on a coil is a chain that is no longer doing anything.
- Run the sixth bundle on a second trip or send it with another truck. A 26-mile run is not worth a scale citation and an out-of-service order.