How to Master the CDL Pre-Trip Inspection: Out-of-Cab Portion

Every day behind the wheel begins before the engine even starts—with a detailed pre-trip inspection. We take this portion of your CDL training very seriously. Not only is the out-of-cab inspection one of the most detailed parts of the job, it’s also one of the most demanding parts of the CDL exam. It requires strong memorization, hands-on confidence, and the ability to explain each component clearly to your examiner. If you’re a more visual learner, we also have a video walkthrough of the inspection led by one of our instructors. Check it out to get a more realistic idea of what you can expect during your CDL training!

At New Sound CDL School in Fife, Washington, we train students every day to perform these inspections with confidence. And with our school boasting an 80% first-time pass rate—the highest in the state—it’s safe to say we know how to help you succeed.

Let’s dive into what the out-of-cab inspection includes, how to approach it step by step, and why this portion of your CDL test is all about confidence, clarity, and knowing your truck inside and out.

‍

What Is the Out-of-Cab Pre-Trip Inspection?

The out-of-cab portion of the pre-trip inspection involves walking through a full inspection of the exterior of the truck, including everything from the headlights and tires to the suspension, brakes, frame, and trailer. Your CDL examiner will expect you to do two things during this inspection:

1. Point to or touch each component.
   
   
2. Describe what you're looking for correctly and clearly.
   
   

Knowing what each part of the truck is called won’t be enough to pass this portion—you have to prove that you understand how the parts should function and how to know if there are issues.

‍

Step-by-Step Walkthrough of the Out-of-Cab Inspection

Here’s a simplified version of what your instructor will teach you at New Sound CDL—and what you’ll be expected to demonstrate on your test.

‍

1. Start at the Front of the Truck

• Lenses and Lights: Check the clearance lights, headlights, and turn signals. Make sure they are clean, not broken or missing, and are the proper color—amber for turn signals and clearance lights, clear for headlights.
  
  
• Vehicle Lean: Check that the truck isn’t leaning to one side. A tilt could mean a suspension problem or a flat tire.
  
  
• Leaks and Puddles: Look under the truck for oil, coolant, or fuel leaks.

‍

2. Inspect the Engine Compartment

• Coolant: Inspect the coolant level. If the engine is cold and the reservoir is clear, it should be between “Add” and “Full.”
  
  
• Oil: Use the dipstick to check that the oil is within the correct range.
  
  
• Power Steering Fluid: Again, use the dipstick to make sure it’s between “Add” and “Full.”
  
  
• Hoses and Lines: Make sure nothing is cracked, worn or leaking. That includes fuel lines, coolant hoses and air lines.

‍

3. Check the Steering System

• Gearbox: It must be securely mounted and not leaking, with all connections tight.
  
  
• Arms, Links, and Rods: They can’t be cracked, worn, or missing cotter pins. Joints also should not be loose.

‍

4. Suspension

• Leaf Springs: Make sure they aren’t cracked, shifted, or missing.
  
  
• Mounts and U-Bolts: All hardware must be secure and not broken or missing.
  
  
• Shock Absorber: Ensure that it’s secure, not leaking, and in good condition.
  
  
• Airbag (if present): It must not be damaged or leaking.

‍

5. Brake System

• Hoses and Lines: No leaks, cracks, or fraying is permitted, and the fittings must be tight.
  
  
• Brake Drums and Linings: These must be free of grease or oil contamination and the linings cannot be dangerously thin.

‍

6. Front Tires and Wheels

• Tread Depth: Tread must be at least 4/32 of an inch on the steering tires.
  
  
• Inflation: Check them with a tire gauge.
  
  
• Condition: No cuts, bulges, or damage are allowed, including exposed cords.
  
  
• Valve Stem: Ensure that they aren’t damaged or missing the cap.
  
  
• Rim: Check for no cracks, bends, or weld repairs, and no rust trails.
  
  
• Lug Nuts: All must be present and tight, without shiny threads or rust streaks.

‍

7. Side of the Truck

• Side Marker Lights: These need to be amber-colored, clean, and not broken.
  
  
• Mirrors: Securely mounted and not cracked or damaged.
  
  
• Battery Box: Secure with clean connections and no excessive corrosion.
  
  
• Fuel Tank: No leaks and securely mounted with a tight cap.
  
  
• Frame: No cracks, holes, or weld damage that needs to be addressed.

‍

8. Drive Tires and Fifth Wheel

• Drive Tires: Tread depth must be at least 2/32 of an inch. Also inspect the inflation levels and sidewall condition.
  
  
• Fifth Wheel Inspection:
  
  
  • Skid Plate and Platform: Properly lubricated and securely mounted.
    
    
  • Apron: Not bent or cracked.
    
    
  • Kingpin: Not bent or damaged.
    
    
  • Locking Jaws: Secured around the kingpin.
    
    
  • Release Arm and Safety Latch: Fully engaged.
    
    
  • Sliding Pins: Fully locked.
    
    
  • No Gap: The trailer should sit flush with the skid plate.

‍

9. Trailer and Rear

• Airlines and Electrical Lines: No air leaks, frays, or exposed wires are allowed. The connections must be seated, locked, and free from damage.
  
  
• Clearance Lights and Reflectors: Clean and not broken—amber up front and red in the rear.
  
  
• Landing Gear: Fully raised, with the pads in good shape and crank handle secure.
  
  
• Trailer Frame and Crossmembers: No cracks, holes, or weld damage.
  
  
• Reflective Tape: Present and properly fixed along the sides and rear of the trailer.
  
  
• Tail Lights and Signals: Red and clean, not missing or broken.
  
  
• Identification Lights: They must be clearly visible.

‍

Pro CDL Tip from Our Instructors

Before you tell the examiner “pre-trip inspection complete,” take 10 seconds to review your checklist. Make sure you didn’t miss any components or forget any descriptions. Remember—it’s your test. Take your time!

‍

FAQs About the Out-of-Cab Pre-Trip Inspection

‍

Is the out-of-cab inspection harder than the in-cab portion?

It isn’t necessarily harder, but there are more components. Both tests are all about repetition and confidence. We train you to master the flow of the inspection so that it becomes second nature. You can learn more about the in-cab pre-trip inspection here.

‍

What happens if I forget a part of the Pre-Trip Inspection?

You may lose points, but you won’t immediately fail if the rest of your inspection is strong. At New Sound, we give you checklists, tips, and plenty of practice on real trucks until you can do it with confidence every time.

‍

Do I have to say the same words as in the Commercial Driver’s Guide?

Nope! You just have to explain each component clearly and correctly. Our instructors help you find the words that work best for you while still hitting all the required points.

‍

How long does the out-of-cab inspection take?

Most students finish in about 15-20 minutes depending on how fast you talk and move. But you should go at your own pace!

‍

Do I need to memorize everything?

Yes—but don’t worry. Our bilingual instructors and real-world training make it easier than you think. With time, this will become second nature. Trust us, we’ve helped countless students gain the knowledge and confidence they needed to ace the CDL exam in one try!

‍

Why Train at New Sound CDL School?

At New Sound, we’ve built one of the best CDL training programs in Washington State—and we back that up with results.

• Highest First-Time Pass Rate: 80% of our students pass the CDL exam on their first try.
  
  
• Expert Instructors: Learn from seasoned drivers with real-world experience.
  
  
• Multilingual Support: Our staff is fluent in Spanish, Russian, and Ukrainian, so you can get the language support you need.
  
  
• Hands-On Training: Practice pre-trip inspections as often as you need with our instructors.
  
  
• Modern Equipment: Clean, up-to-date trucks and a secure, paved lot set our school apart.
  
  
• Job Placement Help: We work with companies like Swift, McLane, and Sysco to help you get hired fast.

‍

Ready to Master the Washington State CDL Exam?

Don’t let the pre-trip portion of your CDL test stress you out. With the right training, tools, and support, you’ll not only pass—you’ll become a safer, more confident professional driver.

At New Sound CDL School, we make the hard parts seem simple. Our programs are designed to help you feel comfortable and confident beyond the wheel of a commercial vehicle. Instead of cutting corners, we teach you the skills you need to master every curve that will come your way.

Apply today, or simply reach out to ask some questions and get a better understanding of what we’re all about.