We’ve all witnessed firsthand the challenges that come with maintaining heavy-duty vehicles during the harsh winter months. One question that frequently comes up among drivers and owner-operators is whether cold weather can affect the coolant level in their trucks.

Answer? Absolutely! Under certain situations, it can even cause the coolant reservoir to fail. Here’s how it all happens, what to expect, and how to keep your cooling system performing properly.

The Impacts of Cold Weather on Coolant Levels

During the winter, it's essential to regularly check the coolant level in the coolant reservoir of your truck, particularly when the engine is cold and has been sitting overnight. The reason for this precaution lies in the nature of liquids and their response to temperature changes. In cold temperatures, the coolant can contract, leading to a noticeable decrease in the reservoir’s coolant level. This contraction might cause the level to drop near or below the "LOW" level line on the coolant reservoir.

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A Low Coolant Level Can Cause Problems

Even a slight cold weather drop in coolant level can trigger the "low coolant" sensor in some trucks. This sensor is designed to alert you before the coolant level becomes critically low, preventing potential damage to the engine. Operating a truck with insufficient coolant can lead to overheating, engine damage, and unexpected downtime––a result that’s costly and inconvenient for any operation.

The Role of the Coolant Reservoir

The coolant reservoir, also known as an overflow tank, expansion tank, or surge tank, serves as the central component of your truck's cooling system. It acts as a storage container for excess coolant that expands when the engine heats up and returns coolant to the system when it cools down. This dynamic process ensures that your engine operates within the optimal temperature range, preventing overheating and allowing for efficient performance.

Cold Weather can be Rough on the Reservoir

The primary reason for coolant reservoir failure is a crack in the plastic housing. Since it’s usually subjected to a lot of heat, the housing can become brittle over time. And in extremely cold weather, when trucks have been parked overnight, the reservoir housing can become downright brittle––and more susceptible to cracking as they expand and contract to meet changes in coolant temperatures. Signs of cracks and coolant leakage typically show up as fluid stains under the engine. Note that cracks can also occur when a cold, rigid reservoir simply can’t meet the flexibility demands of internal pressure and vibration.

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Keeping Cooling System Performance High When Temps Are Low.

Cold weather does indeed have an impact on the coolant level––and on the integrity of the coolant reservoir––in heavy-duty trucks. By understanding the relationship between cold temperatures and coolant contraction, you can take proactive steps to maintain the proper level. And with daily inspections, you’ll have advance warning if stress cracks are starting to form in the reservoir itself.

Remember, regular maintenance is your best defense against weather hazards and challenges. Be proactive, and you’ll have no trouble keeping your truck in top condition throughout the winter season!

Road Choice offers a broad selection of coolants and reservoirs for all applications and engine types. For more information or to schedule a service appointment, call the experts at your nearest Road Choice retailer. You can also order cooling system parts and fluids online, anytime through PartsASIST™ ,delivered directly to your doorstep or available will-call at parts pickup.