Code N
Compatible with: Class A, Class B
Tanker Endorsement
Haul liquid cargo. Command premium pay.
Difficulty
Moderate
Salary Impact
10–25% above non-endorsed positions
TSA Required
No
What Is the Tanker Endorsement?
The Tanker endorsement (code N) is required to operate a commercial vehicle with a tank designed to transport liquid or gaseous materials. This includes fuel tankers, chemical tankers, food-grade liquid tankers, and compressed gas vehicles. Tanker positions consistently pay above standard freight rates.
Who Needs This Endorsement?
Any CDL holder operating a vehicle with a tank or tanks having an individual rated capacity of 119 gallons or more and an aggregate rated capacity of 1,000 gallons or more. This covers fuel delivery, chemical transport, food-grade liquid hauling, and oil field water transport.
How to Obtain It
- 1Pass the Tanker knowledge test at DPS (20 questions; 80% passing score)
- 2Must hold a valid CDL (Class A or Class B)
- 3No additional background check required (unlike HazMat)
- 4Renewal with CDL renewal — no separate renewal process
Knowledge Test Topics
Study Tips
- Understand how liquid surge affects braking and turning
- Learn the difference between baffled and unbaffled tanks
- Study outage requirements for different liquid types
- Review tank inspection procedures — valves, hoses, dome lids
- Understand high center of gravity risks on curves and ramps
Career Impact
Tanker is required for fuel delivery, chemical transport, and oil field water hauling — all premium-paying positions. Combined with HazMat (creating the X endorsement), it qualifies you for the highest-paying CDL loads in Texas.
How Diesel Xtrem Prepares You
Our instructors cover the Tanker knowledge test material in detail, focusing on the liquid surge and inspection topics that DPS examiners emphasize. We help you pass efficiently.