If you want to drive a commercial vehicle, the first step is earning your commercial driver’s license (CDL). In addition to the standard license, there are endorsements you can add that increase the types of vehicles you can operate. There are also CDL restrictions that limit what you can drive or the conditions you can drive in. Understanding what these restrictions are is important to ensure you have the most opportunities available to you after graduating trucking school.
Some CDL restrictions to know:
K Restriction
In order to operate a commercial motor vehicle (CMV) across state lines, you will need to be 21 years of age or older. This is part of federal CDL requirements, so it doesn’t matter what state you earn your license in. However, it is still possible to drive a CMV within your state of residence, as long as you are 18 or older. If you earn your license while under 21, you will have a K restriction, which indicates that your CDL is only valid for intrastate use.
E Restriction
Most passenger vehicles use automatic transmissions, but this is not the case for semi-trucks. Although there are some newer automatic vehicles, most use manual transmissions. Knowing how to switch gears correctly is an important part of safely driving a semi-truck, so you will need to demonstrate this during your CDL test if you plan to drive a manual vehicle. If you take the skills test with an automatic truck, you will have an E restriction on your license. This can severely limit your ability to find a trucking job.
O Restriction
If you take your CDL skills test in a truck with a non-fifth wheel connection or pintle hook, you will have the O restriction placed on your license. This means you cannot operate a tractor-trailer.
Air Brake CDL Restrictions
Traditional hydraulic braking systems use fluid to stop a vehicle, whereas air brakes use compressed air. Air brakes are more effective for stopping larger vehicles, so they are common for semi-trucks and other types of CMVs.
There are not one, but two air brake restrictions. Having either one on your CDL can limit the jobs you can pursue with your license.
The air brake restrictions are:
L Restriction
The L restriction will prohibit you from operating any vehicle with air brakes, whether this is a full or partial system. You will have this restriction if you fail either the written air brakes test or the air brake inspection portion of the CDL skills test. Additionally, you will have an L restriction if you take your skills test with a vehicle that does not use air brakes.
Z Restriction
This restriction prevents you from operating a vehicle with a full air brake system. You will still be able to operate a vehicle with a partial system. If you take the skills test with a vehicle that only has a partial system, the Z restriction will be placed on your license.
Earn Your CDL in Phoenix, AZ
At Phoenix Truck Driving Institute, our skilled instructors will help you prepare for the CDL test. Our programs cover material that helps you avoid CDL restrictions, increasing the number of jobs you can apply for after graduation. We also have a job placement assistance team to get you on the road and earning as soon as possible.
