Reweigh Ticket on I-5: Axle Overload With Nowhere to Put the Weight
At an Oregon DOT weigh station on northbound I-5 you pull onto the static scale at 06:40. The ticket reads: steer axle 11,150 lb; drive tandem 33,600 lb; trailer tandem 35,150 lb; gross 79,900 lb. The scale's sign lists 12,000 / 34,000 / 34,000 / 80,000. Your tractor has a sliding fifth wheel with about 850 lb of unused capacity on the steer axle; the trailer has sliding tandems, and the drives have only 400 lb of headroom. The load is 42,000 lb of palletized paper in a 53-foot van, floor-loaded and strapped, and the shipper sealed the doors at 04:30. The scale house hands you the ticket and a red light. There is a reweigh lane and roughly 20 minutes before the next wave of trucks arrives.
1. Which axles are over their limits, by how much, and is the gross legal?
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| Axle | Reading | Limit | Result |
|---|---|---|---|
| Steer | 11,150 | 12,000 | 850 lb under |
| Drives | 33,600 | 34,000 | 400 lb under |
| Trailer tandem | 35,150 | 34,000 | 1,150 lb over |
| Gross | 79,900 | 80,000 | 100 lb under - legal |
So the gross is fine and one axle group is not. This is a distribution problem, not an overweight-load problem, and that matters because a permit will not fix it.
Read the whole ticket before you move. A scale can flag a bridge-formula violation even when every axle group is under its limit, and Oregon enforces axle, tandem, and bridge limits separately. If the bridge line on the ticket is clear, your fix is purely mechanical.
2. Why is simply sliding the trailer tandems rearward not a clean fix here?
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Sliding the trailer tandems rearward lengthens the distance between the kingpin and the trailer axles, which unloads the trailer tandem and puts that weight onto the tractor's drive tandems through the fifth wheel.
You need to shed 1,150 lb from the trailer tandem. The drives have 400 lb of room. One hole of tandem slide typically moves several hundred pounds, so any single slide big enough to legalize the trailer will put the drives over - you would trade one red light for another.
The fix has to be sequenced. First create capacity where there is room: slide the fifth wheel forward to move weight onto the steer axle, which has 850 lb of headroom. Then slide the trailer tandems rearward one hole at a time. Every adjustment affects more than one axle, which is exactly why you change one thing and reweigh before changing anything else.
3. Give your step-by-step plan at the scale and name one shortcut you must not take.
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Plan:
- Read the full ticket, including the bridge line, and note which axle is over.
- Slide the fifth wheel forward one notch. Reweigh.
- Slide the trailer tandems rearward one hole. Reweigh.
- Repeat in single steps until all axle groups and the bridge line are legal with margin. Do not tune to exactly 34,000 lb - a few hundred pounds of cushion covers scale variation and fuel burn.
- If the hardware cannot get you legal, ask about offloading at the scale or a nearby dock, or contact ODOT about an overweight permit for the remaining distance. Both are legitimate; neither is free, and the load is the shipper's problem to solve with you.
Do not: leave the scale after a partial correction and 'fix it down the road.' You will be reweighed, the citation will be written at the higher weight, and your carrier's safety record absorbs it.