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“L” is for Airbrakes?

Air-brakes.  One of the most confusing words for some truck drivers.  All drivers are expected to conduct a pre-trip inspection.  Many are even expected to know how to adjust their own slack adjusters.  But how many can tell another what the definitive criteria is when an air-brake restriction is permitted?  Wait… restriction? Isn’t it an air-brake endorsement?  Read on if you’re confused already.

Everyone who has passed the CDL test, and even some of those who’ve failed, have encountered the reference to 60, 100 and 125 psi, maximum push stroke, brake lag, etc.  The ITEA and its certified officers constantly receive questions regarding which drivers are in need of an air-brake endorsement, but here’s the truth: Illinois does not issue an air-brake endorsement.

Endorsements to CDLs are limited to those the Federal Motor Carrier Safety Administration allows, which does not include air-brakes.  Hence Illinois’ air-brake restriction.

If a driver chooses not to take or pass the air-brake portion of the Illinois CDL written and skills tests, they are issued a “L” restriction on their license.  The confusing portion of the Administrative Code which governs this restriction is that it permits drivers with an “L” restriction to still drive some vehicles with air-brakes.  Here’s how:

Suppose a driver is operating a Commercial Motor Vehicle (CMV) which requires a Commercial Driver’s License.  If the CMV had air-brakes the driver would not be permitted to operate it if their CDL had an “L” restriction.  However, if a driver held an “L” restricted CDL, and was operating a vehicle which had air-brakes but which did not meet the criteria to be considered a CMV, there would be no violation.  This is because the “L” restriction applies only to Commercial Motor Vehicles.

Similarly, the Secretary of State will not apply an “L” restriction to any non-commercial license.  This may confuse some because this leads to a shared misconception.  It is commonly believed that if a truck has air-brakes it is then a CMV.  Not so.

While, often times a truck is of such a size it is manufactured with an air-brake system, it likely fits the weight requirements for CMVs. However, there are certainly exceptions.  If a driver with a non-CDL license is found operating a truck with air-brakes, and the truck does not meet the criteria for being considered a CMV, there is no violation.

Despite a violation for operating a CMV with a “L” restricted CDL being a petty offense,  do not be surprised if you get parked by an officer for this violation.  Even though you cannot be taken into custody, officers are permitted to restrict further operation of the truck for this violation.

The letter “L” can just as equally represent “liability”. Liability to the driver if he chooses to operate the truck. Liability to the officer who enables a driver to continue driving when Illinois has deemed he should not be operating the vehicle.

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