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We’ve all seen them. They’re everywhere once construction season kicks off in the spring. The cops call them “bombers” and the industry calls them dump wagons or dump trailers. Pick whatever moniker you like, but they are probably one of the most recognizable combinations of vehicles on the road. They’re big. They’re powerful. They’re dirty. They’re workhorses. They are the persona of American trucking. The big question is why does a truck so commonplace on the road cause so much confusion in the law?

To qualify as a 5-axle SHV as listed in 625 ILCS 5/15-111(a)(10), certain conditions must be met:

1. Five axles This is easy enough to understand, but the axle configuration is set by law. The single steer axle must be followed by two sets of tandems. If the two axles on the trailer are spread more than 96”, it is not a tandem and the combination does not qualify. If there are six axles on the ground, it does not qualify. But if the combination has a sixth axle in the air, it does qualify.

2. Semi-tractor tractor trailer combination The ITEA has fielded questions if a straight truck-full trailer combination meets the criteria and the answer is no. A straight with 5 axles does not qualify either.

3. Overall wheelbase of 42’ or less The wheelbase is measured from the center of the first axle to the center of the last axle. The 42’ dimension is an absolute…if the wheelbase exceeds 42’ by even one inch, it does not qualify.

4. Both the power unit and the trailer must be registered in Illinois The power unit can be registered with Illinois flat weight plates or apportioned from another state as long as the cab card lists Illinois. The semi-trailer can either bear Illinois semi-trailer plates or have apportioned trailer plates with Illinois listed.

5. Minimum wheelbase from axles 2-5 of 18’6” if the trailer was manufactured after 17 Aug 2001. The idea here is that older trailers were manufactured shorter, and the industry standard for new trailers is longer.

Dump trailers aren’t the only qualifying configuration though. Fuel trailers, roll-off hoists, intermodal chassis, lumber flatbeds – even cement mixers – may all qualify as well. If the combination meets all the conditions above, the power unit may be registered as a Special Hauling Vehicle. This is a $125 permit that is assigned to the power unit on the registration card. However, the SHV does nothing for the trucks registered weight. This is an anomaly in the law when a registration provision from Chapter 3 of the Illinois Vehicle Code affects legal weight in Chapter 15.

A qualified combination with an SHV is allowed 20,000 pounds on a single axle, 34,000 pounds on a tandem, and 72,000 pounds gross. There can be no application of the Federal Bridge Formula for any series of axles.

If the power unit is registered with flat weight or apportioned plate from Illinois, the SHV status is listed on the registration card as well as the SOS data return for police officers. If the power unit is registered with a foreign apportioned plate, the SHV registration card will accompany the cab card. Sometimes truck owners transfer registration from one truck to another and forget to fill out the SHV transfer form…its free to do, but very expensive not to do!

Exceeding the weight limits of the SHV does not void the SHV either. What is legal is legal. A similar situation is when a truck exceeds the weight limits of a valid overweight permit. The permit is not void, and only the excess weight can be cited. For example, under the Federal Bridge Formula a bomber without a SHV may only receive 67,000 pounds gross weight, but the SHV raises that to 72,000. If on the scale the combination weighs 76,000 pounds, the citation is for 4,000 pounds over, not 9,000 pounds over.

Like many things in truck law, reading into it too much makes it more complicated. The plain language of the law is all you need.

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