Quick Tips to Pass Your Next Trailer Inspection

Trailer inspection doesn’t have to be the scariest part of your day. Pass with confidence and ease thanks to these tips and tricks from the experienced and knowledgeable truck mechanics at M&L Truck Service!

Check Tire Pressure and Tire Tread Depth

One of the most common reasons trucks and trailers are put out of service by the Maryland Department of Transportation (DOT) is because of tire pressure or tread depth. While we don’t offer tire services at M&L Truck Service, we want you to be aware that this is a very common pitfall that can lead to trailers not passing inspection.
 
Many trailers are equipped with tire auto-inflation systems that keep the tires at 105 PSI. That’s generally a best-practice inflation level, but always check your trailer specs to be sure. When you have a trailer that automatically maintains tire inflation levels, you’ll notice that your auto-inflation indicator light may come on when you hook up your trailer. If that light stays on all the time, you have a tire that needs service.
 
Tire tread is considered urgently low when it reaches a depth of 2/32”. Remember that the “penny test” is helpful for a lot of vehicle tires, but truck tires may be deeper and will need a different method of measurement. Check your inside and outside trailer tire tread monthly using a tread measurement tool to get an exact measurement.
Image of a semi truck trailer tire inspection using an air pressure gauge to measure tire pressure in pounds per square inch (PSI).

Inspect All Trailer Lights During Pre-Trip Checks

It is very easy for drivers to not realize that their rear lights are out, so it’s important to test them often. You’ll need to test your brake lights, turning signal, and all other lights on your trailer to ensure that the bulbs are still good, and the wiring is connected properly. It’s not just for your trailer inspection, either — it’s not safe to not be able to communicate with other drivers via your tail lights!

Ensure All Trailer Components Are in Working Order

There are a lot of parts that are checked during a trailer inspection. They include the hitches, coupling chains, doors, brakes, fenders, suspension, and springs. While the lights and tire pressure are pretty easy to check yourself, most things beyond that might get a little more technical and require more time than you can afford to spend on each trailer.
 
At M&L Truck Service, we can complete your trailer inspection and fix anything that might be wrong — right in the same shop. We also offer ongoing truck maintenance services to help prevent these types of problems before they arise. We’re thrilled to help you pass with these tips, and can even perform your official Maryland DOT trailer inspection. Just give us a call!
Image of trailer inspector with a clipboard, kneeling by a truck tire and checking for damage.

Trailer Inspection Services and More

We are proud to offer trailer inspection services, as well as DOT truck inspectionsMaryland State Inspections, and Crane inspections. Contact our team of experienced heavy duty commercial truck and trailer experts for all your fleet maintenance and inspection needs.

Meet M&L Parts Specialist, Eddie James
Meet M&L Parts Specialist, Eddie James

Eddie is one of our newest team members, having started in 2024. His first car was a '77 Camaro and his favorite tool is the air grinder.