As temperatures begin to drop and winter approaches, fleet operators must take steps to ensure their vehicles are ready for the challenging conditions ahead. Winter can be tough on both vehicles and drivers, but with proactive preventive maintenance (PM), you can minimize breakdowns and keep your fleet running efficiently. 

Leveraging insights from industry experts at Cox Automotive, here are six critical areas to address as you winterize your fleet.

1. Battery & Electrical System Health

Winter weather is notorious for draining batteries, making it harder for vehicles to start. Cold temperatures slow down the chemical reactions inside the battery, reducing its output. Jeffrey Nichols, a senior diesel technician from Fleet Services by Cox Automotive advised, "Cold starts are tougher on batteries, and it's essential to test them before the real winter hits." Perform load tests, clean terminals, and ensure charging systems are in good working order.

For EV fleets, Terry Rivers, a Fleet Services expert in EV training, recommended preconditioning your batteries by warming them before starting a trip. 

"Preheating your EV battery can enhance its range and efficiency, helping the vehicle perform better in cold conditions," Rivers explained.

2. Air Dryer System Maintenance

Air dryers play a crucial role in ensuring the reliability of your fleet's braking system. In cold weather, moisture in the air system can freeze and cause malfunctions, leading to potentially dangerous breakdowns. 

"Freezing in the air system is one of the most common winter failures we see,” said Nichols. 

Routine checks, draining air tanks, and maintaining air dryers to OEM standards are essential to prevent winter air system issues.

3. Cooling System Check-Up

One of the most critical winter maintenance tasks is ensuring the cooling system is prepared for low temperatures. Check antifreeze levels to confirm the proper water-to-coolant mix, which should be 50/50. 

Nichols emphasized checking diesel coolant additives (DCA) for proper levels to prevent corrosion and engine wear. Additionally, inspect belts and hoses for wear and test block heaters to ensure they are operational, especially in diesel engines.

4. Driver Preparedness & Cab Safety

Winter readiness goes beyond the mechanical aspects of your fleet. Drivers need to be fully prepared for the conditions they might face. 

Larry Fowler, senior manager of vehicle operations support at Fleet Services, stressed the importance of stocking emergency supplies in the cab. 

“Breakdowns in cold weather are not only inconvenient but dangerous,” Fowler explained. 

Ensure wiper blades are functioning, heated mirrors (if equipped) are working, and the washer fluid reservoir is full. Also, make sure the vehicle safety kit is complete with emergency blankets, warm clothing, and other essentials.

5. Fuel Treatment Strategy

Fuel gelling is a major concern during the winter, particularly for diesel vehicles. Fowler said fleet operators should use blended fuels or additives to keep fuel flowing freely in freezing conditions.

Ensure fuel heaters are operational and consider region-specific fuel blends if your fleet will operate in especially cold weather areas. Preventing fuel from gelling is crucial to keeping your vehicles on the road.

In EV fleets, parking vehicles indoors or in covered spaces is another strategy to maintain battery health in cold weather, as it helps protect against freezing temperatures that can degrade battery performance.

6. Tire Condition & Pressure

Tire maintenance is often overlooked in cold weather, but ensuring your fleet is ready for winter road conditions is critical. Tire pressure decreases in colder temperatures, which can lead to reduced traction and uneven wear. 

"Closely monitor tire pressure and adjust it as temperatures drop to ensure safe and smooth winter travel,” suggested Ben Deisig, a senior diesel tech with Fleet Services.

Proper tire maintenance helps ensure your fleet maintains an optimal grip on icy or snow-covered roads, enhancing both safety and performance.

Preparation is the Best Defense Against Winter Fleet Troubles

These expert-backed tips from FleetNet America and Cox Automotive remind us that preparation is the best defense against winter fleet failures. Start your maintenance early, focus on critical systems, and equip your drivers with the knowledge and tools they need to navigate harsh conditions safely.

About the Author: Mike Hagaman is senior director, customer engagement, FleetNet America. This article was authored and edited according to WT editorial standards and style. Opinions expressed may not reflect that of WT.