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Doubles Troubles

There’s old expression called “getting the cart ahead of the horse”. In the modern world, the horse represents the truck, and the cart is the trailer. It’s always a bad situation when a non-motor vehicle leads the power unit. Legislation can be like that too. In Washington DC, legislators are crafting a new truck length bill which exceeds industry standards, while back home in Illinois legislators are just trying to get truck length law out of the 1950s!

At the federal level, a small group of the biggest national carriers are pushing for controversial new federal legislation which would allow the maximum trailer length for double trailers to be extended from the industry standard 28’6” to 33’. The Illinois Truck Enforcement Association is not supporting or opposing the idea, but instead critically thinking through how this affects Illinois.

Truck-tractors towing double semi-trailers is a national standard. Semi-tractors towing triple semi-trailers is not. Triples are not allowed in Illinois. Many times police officers ask “why then does Illinois have a “T” endorsement for CDLs?” The reason is because CDLs are federally mandated and an Illinois driver may legally operate triples outside of Illinois.

When double semi-trailers (or double bottoms) are being towed in Illinois, the maximum length for each trailer is 28’6”. As previously mentioned, this is the industry standard for this configuration. Several states allow “western doubles”, “turnpike doubles” or “rocky mountain doubles” which allow double semi-trailers with individual lengths as long as 53’.

The key thing to understand about nearly sixty years of federal truck legislation is that the law only applies to federal highways known as the National Network (NN). This highways may be owned and maintained by the individual states, but dedicated funding from the Federal Highway Administration means they have jurisdiction over size and weights.

Study this timeline for the common theme:

  1. In 1956, Illinois instituted the “State Bridge Formula” for weight. In 1974, the federal government implemented the “Federal Bridge Formula” for weight on the NN, to which Illinois did not comply until 1986! It took until 2010 for Illinois (the last state in the Union) to allow the same weights on local roads.

  2. In 1976, the federal government authorized 102” for width on the NN. Illinois did not mandate the 102” width on local roads until 2010.

  3. By 1982, the federal government forced each state to lock in the maximum length of semi-trailers using the Surface Transportation Assistance Act. Illinois chose 53’, but still has not allowed the overall length of truck-tractor semi-trailers to exceed 55’ on local roads (only 2′ long tractors may lawfully tow these trailers on local roads).

Is this repeating cycle of “industry standard yields change in federal regulation but not state regulation” not plainly obvious?

The difference with double semi-trailers is that 33’ footers are not the industry standard. The sect of industry leading this push is attempting to redefine the loose meaning of “industry standard” as it applies to doubles. That is the cart being put ahead of the horse.

While Illinois has managed to play catch-up in regards to width and weight, Illinois length laws are almost old enough to collect social security. The federal government may very well mandate 33’ semi-trailers for doubles on the NN, and Illinois may very well comply – for the NN. That does not mean Illinois will comply for local roads. It’s probably a safe bet, based on the legislative history of Illinois, it will take a minimum 20 years before uniformity would be mandated.

Under current Illinois law, if a combination of doubles travels on a local road (barring any reasonable access provisions), the maximum overall length is 60’ from bumper-to-bumper. Do the estimated math:

Tractor (bumper to kingpin) = 15” Semi-trailer #1 = 28.5” Space between trailers = 4’ Semi-trailer #2 = 28.5” Total = 76’

The truth is industry standard doubles cannot be legal on local roads in Illinois under current law, yet there is a federal push to increase the limits. Progress is good, and legislation which helps industry be more profitable is good too. However, at what point should the focus be on retroactive modernization and not trailblazing?

The bigger priority for making Illinois less business repellent and more inviting would be to increase the overall truck-tractor semi-trailer length from the 1956 standard of 55’ to at least 65’. This would allow the very 53’ trailers declared by Illinois as “standard” in 1982 to be legally hauled with a day-cab.

That’s right, Illinois’ SB 1390 does just that. Yes, Illinois needs to be more proactive, but Washington DC could afford to slow down a little too.

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