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Cement Mixers – Week 2

Cement is simple. Mix a few aggregates and water, load and spin in a truck, pour out on a jobsite, and then leave to harden like rock. But mixer law is not always so simple. Last week this blog spent time discussing the weight exceptions afforded cement mixers in Illinois. But that is not the end of unique laws that pertain to cement mixers. Cement mixers also have some unique aspects of their configuration that most trucks don’t have and it changes the method that police use when weighing them. Cement mixers also have an extra provision in how much grace weight they receive before the load must be legalized.

It is hard to find a 4 or 5-axle cement mixer in Illinois that does not have a pneumatic axle which raises or lowers through a mechanical process. Most 4-axles mixers have a trailing axle on the rear of the vehicle that lifts when the truck is empty as the extra axle is not needed to cover the weight. Many 5-axle mixers have either a trailing axle or an intermediate axle, or both.

What makes this important is the method police officers use when weighing the mixer. Adjustable axles are meant to self-regulate based on the PSI (pounds per square inch) set by the operator. The goal is for the truck to keep balanced weight between the axles at all times. Because of this, when a truck goes over bumps, rail crossings or curbs, the weight equalizes between the axles keeping the truck upright.

Unfortunately a rumor has circulated in the truck enforcement community for years that cement mixers cannot be weighed on portable scales. This is untrue, but if a police officer weighs a mixer on portables, all axles must be level. This is accomplished by the use of extra scales or equal height dummy pads. The police officer should note the PSI of the pneumatic axles at the time of stop, and the air gauge needs to return to that setting for each weight taken. If neither of these things are done, then the weighing is inaccurate.

Remember last week when you learned that cement mixers registered as a Special Hauling Vehicle (SHV), with a tandem spread out between 72” to 96”, receives 36,000 pounds on the tandem instead of the typical 34,000 pounds? This special weight allowance applies to mixers of either the 3 or 4-axle variety…but the extra provisions don’t stop there!

Under 625 ILCS 5/15-112(b), any police officer who finds an overweight violation SHALL require the driver to reduce the weight of the load until it is legal. However, cement mixers described in the paragraph above are forgiven of this requirement up to 4,000 pounds overweight. The police officer may still write the overweight citation if the axle or gross weight exceeds the statutory 2,000 pounds grace weight, but he must issue the citation and release the vehicle if it is less than 4,000 pounds overweight on either axle or gross.

This is for good reason. A load of wet concrete is worth a lot of money to the customer. If the load is held and allowed to dry in the mixing drum, the entire drum is waste. The cost to replace the drum is extremely expensive. The General Assembly is not absolving the concrete industry of all responsibility, but they also recognize the economic impact the cement industry makes. The goal of this article is not to agree or disagree with this law, but to relay what the truth is.

Lastly, the assumption is that most cement mixers require a driver who holds a valid Commercial Driver’s License (CDL). Here’s the facts: a cement mixer is a tank. The “tank” in this instance holds a quantity of “liquid”. Most CDL vehicles with a tank similar in size to a cement mixer will require an “N” tanker endorsement. This is not true for cement mixers though. A CDL holder operating a cement mixer is NOT required to have a tanker endorsement while in that vehicle. Will you find this in the IVC? No. But the IVC has adopted and is bound by the CDL laws of the Federal Motor Carrier Safety Regulations, and that code lifts the tanker endorsement requirement for CDL’s.

…and for our card-carrying ITEA members, log into the discussion forum and take a free, online quiz to challenge your mixer legal understanding!

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