Earning your commercial driver's license (CDL) is the first step towards a flourishing career as a truck driver. The demand for commercial driving workforce is huge: a lot of employers go to great lengths to find CDL drivers. But to advance your career, certain endorsements should be earned and restrictions should be removed. Whether you have a Class A, Class B, or Class C CDL, you will want to know about the different endorsements and restrictions you will face.
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CDL Endorsements
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CDL endorsements are essential for commercial drivers to operate special types of commercial motor vehicles (CMVs). Outside of the Class A, B, or C CDL requirements, there are additional tests to obtain the following federal CDL endorsements.
Note: There may be additional endorsements depending on the state you legally operate in.
H
The H endorsement is required to operate a vehicle that contains hazardous materials. A written knowledge test is needed to obtain a hazmat endorsement.
N
The N endorsement allows CDL drivers to operate a tank vehicle (a vehicle that transports liquids or gasses). A written knowledge test is required to obtain a tank vehicle endorsement.
P
The P endorsement is needed to operate a vehicle that seats 16 or more people, including the driver. A written knowledge test and road skills test is required for a passenger endorsement.
S
The S endorsement allows drivers to operate a school bus. Prior to obtaining an S endorsement, a P endorsement must be earned. A written knowledge test, road skills test, separate application forms, fees, and a background check is required for a school bus endorsement.
T
The T endorsement is necessary for CDL drivers looking to tow a double or triple trailer. A written knowledge test is required to obtain a double/triple trailers endorsement.
X
The X endorsement is a combination endorsement for tank vehicles and hazardous materials. A written knowledge test is required to earn a combination tank vehicle and hazmat endorsement.
CDL Restrictions
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CDL restrictions prohibit the operation of certain types of CMVs. The restriction code is placed on the CDL.
Note: There may be additional restrictions depending on the state you legally operate in.
E
An E restriction prohibits CDL truck drivers from operating a vehicle with a manual transmission. If a skills test is performed with an automatic transmission, an E restriction will be issued.
L
An L restriction prohibits the the operation of a vehicle with a full air brake system. If the skills test isn't taken with a full air brake system, air brake systems aren't properly checked, or air brake system components aren't properly identified, an L restriction will be issued. An L restriction will also be issued to drivers that do not pass the air brakes knowledge test.
M
An M restriction indicates that a driver can only operate a Class B or C passenger vehicle or school bus. If a driver has a Class A CDL, but obtains their passenger endorsement (P) or school bus endorsement (S) in a Class B vehicle, an M restriction will be issued.
N
An N restriction indicates that a driver can only operate a Class C passenger vehicle or school bus. If a driver has a Class B CDL, but obtains their passenger endorsement (P) or school bus endorsement (S) in a Class C vehicle, an N restriction will be issued.
O
An O restriction prohibits drivers from driving a Class A vehicle with a fifth wheel connection. An O restriction will be issued if a driver takes the skills test in a Class A vehicle that has a non-fifth wheel connection or pintle hook.
V
A V restriction is issued when a driver has a medical variance, reported by the Federal Motor Carrier Safety Administration (FMCSA). A medical variance includes diabetic, hearing, seizure, or vision impairments.
Z
A Z restriction prohibits drivers from operating a CMV equipped with full air brakes. A Z restriction is issued if the driver doesn't take the test with an air over hydraulic brake system.