Overweight Trailer Tandem and Insufficient Securement
At a weigh station on I-5 near Medford, your 53-foot van scales: steer axle 11,900 lb, drive tandem 33,800 lb, trailer tandem 35,600 lb, gross 81,300 lb. The trailer tandems are set 10 feet from the rear. The load is 24,000 lb of canned goods on 20 pallets; 6 pallets are loaded at the rear doors, and the rest are forward. You have eight 2-inch straps, each labeled 1,100 lb working load limit, over the rear six pallets only. The steer tires are rated 6,000 lb each; drive and trailer tires are rated 5,000 lb each. Oregon and federal limits apply: 20,000 lb per single axle, 34,000 lb per tandem, 80,000 lb gross. You must decide which limits are violated, whether the securement is legal, and what adjustments you can make before leaving.
1. Which weight and securement limits are violated? Show the arithmetic.
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The trailer tandem at 35,600 lb exceeds the 34,000-lb tandem limit by 1,600 lb. Gross at 81,300 lb exceeds 80,000 lb by 1,300 lb. The steer axle is under its 12,000-lb tire rating at 11,900 lb but has only 100 lb of headroom. The drive tandem at 33,800 lb is legal but has only 200 lb of headroom. Securement is also illegal: eight straps at 1,100 lb WLL give 8,800 lb aggregate WLL. For 24,000 lb of cargo, the aggregate WLL must be at least 12,000 lb, half the cargo weight. The straps also cover only the rear six pallets, not all cargo.
2. Can sliding the tandems or moving the load fix the problem? What is the practical correction?
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You cannot fix this by sliding the trailer tandems forward: that would shift weight onto the drive tandem, which has only 200 lb of capacity. Sliding them rearward would add weight to the already overloaded trailer tandem. Moving cargo forward would also load the drive axles. The practical fix is to offload at least 1,600 lb from the trailer tandems and at least 1,300 lb from gross weight. Removing about two pallets from the rear satisfies both, then re-scale. After that, secure every pallet with enough tiedowns to meet the aggregate WLL, using additional straps or a securement system, and recheck axle and gross weights.
3. What final checks should you complete before leaving the weigh station?
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Get a new scale ticket showing steer, drive, trailer, and gross within limits, and confirm axle spacing and bridge limits if applicable. Check tire ratings and inflation. Re-secure the load with at least 12,000 lb aggregate WLL for 24,000 lb of cargo, with tiedowns attached to the trailer and placed over or around the cargo to prevent forward, rearward, and lateral movement. Use edge protection if straps contact sharp edges. Recheck after the first few miles because cargo can settle. Do not move until the weight and securement violations are corrected.