Trailer winterization: Dry van systems to inspect during

To avoid this, fleets should make sure their trucks and trailers are ready for the cold. And there’s no time like the present to remind maintenance teams to pay a little extra attention to their dry vans before the weather takes a turn for the worse.

To get started, here are seven systems to inspect for winter readiness.

Air system

During winter, if water gets into the air system and freezes in valves or air lines, drivers may encounter problems with their transmission, braking, or emissions systems. Instead, technicians should drain a truck’s air tanks so moisture doesn’t accumulate.

“Moisture building up in the air system is a recipe for trouble,” said Jon Karel, senior vice president of marketing and sales at Fruehauf, a manufacturer of dry vans. “Sure, you can add in-line air filters or in-line air dryers, or even use anti-icing agents. But no matter how you tackle it, checking your air dryer’s performance and draining any water from the air tank should be standard practice before cold weather hits.”

Electrical system

Fleets should also be sure to check their vehicle batteries for temperature drops, especially since both hot and cold weather can decrease their efficacy.

In 2021, Odyssey Battery reported that oil can thicken when temperatures drop, making the battery work harder to start the engine. But if summer heat has caused a battery’s electrolyte to evaporate, this can quickly lead to starting issues.

Instead, regularly check batteries, wiring, and connections to make sure everything is working correctly and looking good, free of moisture, corrosion, and fraying. And don’t forget about things like liftgates and reefer units that have their own battery systems.

Lights

Days get shorter during the fall and winter, so a dry van’s lights get used more and become more important than ever, even as it gets easier for inspectors to spot when there’s a problem.

“Lights are always key for passing a DOT inspection,” Karel reminded. “But with less daylight on a driver’s side, making sure every light is working should be high on a maintenance team’s list.”

Additionally, corrosion can be an especially big issue for electrical systems during winter. While winterizing your dry van, be sure to make sure all your lights are working, and if one isn’t, first check for any physical damage to lights and circuits. Then make sure connections don’t have a corrosive buildup. Also, when testing your light’s voltage, always take the wiring harness out of the back to check its current, instead of sticking a hole in the harness coating, which can invite additional corrosion.

Brakes

Just like with lights, a dry van’s braking system is always a critical inspection point. Karel said technicians should double check that the electrical cord and in-cab circuit breakers are working correctly.

“When roads get slick and you need your ABS to do its job, you’ll be glad you took the time to make sure everything is ready for the season,” Karel said.

This includes carefully checking your brakes for any cracks, rust, or wear, and keeping an eye out for grooved rotors and drums. Then, it’s never a bad idea to make sure your brakes are properly adjusted, too.

Tires

Staying on top of tire inspections is especially critical in colder weather, as good treads will help your drivers stay on the road.

Closely monitor tread depth, flat spots, and irregular wear, and pay close attention to tire pressure. Make sure you’re maintaining the right pressure based on the temperatures your trailers will be operating in, and be prepared to refill earlier than anticipated if your dry van is traveling between different ambient temperatures.

Finally, rotate trailer tires as necessary when mild wear is observed.

Look for leaks

Inspect around the trailer for air gaps and leaks, especially in the roof. You never want water making its way into a trailer. But in winter, that water could end up freezing, causing a host of safety issues as well as compromising the cargo being transported.

A quick method is applying a soapy mixture to the exterior of lines to look for bubbles, though a diagnostic smoke machines are a more diverse and accurate option for seevral systems on the tractor and trailer.

Keep it clean

But electrical systems aren’t the only places technicians should look out for road-chemical-induced corrosion. The tractor-trailers themselves will likely encounter plenty of anti-icing and de-icing chemicals, which are abrasive and can lead to rust and corrosion.

To cut down on this corrosion, wash your trucks and trailers regularly, at least every week, with particular focus on the undercarriage where road chemicals can accumulate. A good truck detergent and pressure washer will often do. For added protection against corrosion, you could also add a flash corrosion inhibitor to the detergent, or an underbody coating if a trailer is going to be spending a lot of time in harsh winter environments.

One thing to keep in mind with washing is that some trailer manufacturers actually advise against using a pressure washer. They say water can end up seeping into areas you don’t want it to, which could end up freezing during the winter and lead to rust problems later on. If using a pressure washer, use it carefully and avoid using too much pressure, if possible.

There are many other steps to take to get your dry vans prepped for winter weather. But these words of wisdom are a great place to start.