Preventing Gelling with Intelligent Idling

Jeff Lynch
January 8, 2025
6 minutes read

When winter temperatures plummet, fleet operators face one of the harshest challenges in cold-weather operations: diesel fuel gelling. Gelling can immobilize vehicles, cause safety concerns, and lead to substantial downtime and maintenance costs. While proactive measures like fuel additives and winterized diesel are common, intelligent idling technology offers a modern solution to this persistent problem.

In this post, we’ll explore how diesel gelling occurs, its impact on fleet operations, and how intelligent idling technology can mitigate these risks, ensuring safer, more efficient, and cost-effective operations.

Understanding Diesel Gelling

Diesel fuel gelling occurs when paraffin wax, naturally found in diesel, solidifies in freezing temperatures. This process typically begins at a fuel’s cloud point, which is around 32°F for standard diesel, but can vary depending on the blend. The gelled wax clogs fuel filters and lines at lower temperatures, preventing fuel from reaching the engine.

Key Facts About Gelling:

Diesel gelling typically starts around 20°F and can fully block fuel systems at 10°F or lower
Fuel filters are often the first component to clog, leading to immediate engine shutdown
Gelling incidents result in costly repairs, towing expenses, and unplanned downtime

The Impact of Gelling on Fleets

Gelling isn’t just a seasonal challenge. It’s a critical threat to fleet efficiency and safety. Beyond the hassle of clogged fuel lines, gelling can lead to cascading operational delays, costly repairs, and heightened safety risks that compromise driver well-being and delivery timelines.

Operational Downtime

Imagine this scenario: A long-haul driver parks overnight in subzero conditions. The truck won’t start the next morning because gelled fuel has blocked the fuel lines. The vehicle is immobilized and requires roadside assistance or towing to a repair facility. For fleet managers, this means lost productivity and missed delivery schedules.

The average cost of unplanned downtime for a single truck can reach up to $1,000 per day, factoring in lost revenue and recovery expenses.

Increased Maintenance Costs

When gelling occurs, resolving the issue often involves draining and flushing the fuel system, replacing clogged filters, and, in severe cases, repairing engine components. These costs add up quickly, straining already tight budgets.

Preventable maintenance issues like gelling can account for 30% of a fleet’s annual maintenance budget.

Safety Risks

A stranded truck isn’t just a logistical problem—it’s a safety concern. Drivers can be left in hazardous conditions without reliable access to heat, fuel, or emergency services. The risk increases in remote or icy areas where response times are slower.

Traditional Solutions to Diesel Gelling

Traditional methods to combat diesel gelling have focused on prevention through additives, specialized fuel blends, and manual interventions. While these approaches can be effective, they often come with additional costs, labor demands, and inconsistencies that leave fleets vulnerable to disruptions.

Winterized Diesel and Additives

Most fleets use winterized diesel fuel, which lowers the temperature at which gelling occurs. Anti-gel additives are another common tool, preventing wax particles from solidifying in freezing conditions. While effective, these measures are not foolproof and require diligent monitoring and maintenance.

Block Heaters

Block heaters keep engines warm overnight, reducing the likelihood of gelling. However, they require access to external power sources, which isn’t always feasible for long-haul drivers or remote locations.

Manual Idling

Many fleets instruct drivers to idle their engines during cold weather to maintain fuel flow and prevent gelling. While this method works, it’s far from efficient. Excessive idling wastes fuel, increases emissions, and accelerates engine wear.

How Intelligent Idling Reduces Gelling Risks

Intelligent idling technology automates maintaining optimal engine and fuel system temperatures, eliminating the need for manual idling. By cycling the engine at precise intervals, intelligent idling keeps fuel flowing without unnecessary fuel consumption or wear on the vehicle.

Maintenance Benefits

By preventing gelling, intelligent idling minimizes the risk of emergency repairs, reduces strain on critical engine components, and extends the vehicle’s lifespan.

Cost Savings

Efficient idling drastically reduces fuel consumption compared to traditional methods, translating into significant cost savings over the winter season.

Fleets can save up to $6,000 annually per truck by reducing unnecessary idling.

Improved Safety

With intelligent idling, drivers can rest assured that their vehicles will start reliably, even in extreme weather. This reduces stress and ensures they aren’t stranded in dangerous conditions.

A Real-World Scenario

Consider a fleet driver parked overnight in Montana during a particularly harsh winter storm. Temperatures drop to -10°F, and traditional measures like anti-gel additives aren’t enough to keep the fuel from gelling.

Without intelligent idling:

The driver wakes to find the truck won’t start, delaying their delivery and requiring costly towing and repairs.
Fleet managers scramble to reroute other trucks to cover the missed shipment, increasing operational inefficiency.

With intelligent idling:

The system automatically cycles the engine to maintain optimal fuel temperatures, preventing gelling and ensuring a smooth start the next morning.
The driver safely resumes their route, avoiding delays and keeping customer commitments intact.

The Broader Impact of Intelligent Idling

Intelligent idling goes beyond reducing diesel gelling—it transforms fleet operations by enhancing fuel efficiency, reducing maintenance needs, and improving driver safety. This comprehensive approach addresses immediate challenges and long-term operational goals, positioning fleets for sustained success.

Reduced Environmental Footprint

Intelligent idling optimizes fuel consumption, reducing greenhouse gas emissions associated with excessive idling.

A single truck can save approximately 1,200 gallons of fuel annually by adopting intelligent idling practices.

Enhanced Driver Retention

Reliable vehicles reduce driver frustration and downtime, contributing to job satisfaction and retention, key metrics for fleet managers in a competitive labor market.

Long-Term Operational Resilience

By integrating intelligent idling into their operations, fleets position themselves as reliable partners in industries where on-time performance and safety are critical.

Taking the Next Step Toward Winter Readiness

Diesel gelling is a preventable problem, but it requires a proactive approach. Intelligent idling is not just a technological upgrade—it’s a strategic investment in your fleet’s safety, efficiency, and profitability.

Learn more about how intelligent idling can transform your fleet’s winter operations. Schedule a call with Idle Smart today and take the first step toward operational excellence.

CCJ Shares 2025 Roadcheck Results

The results are in from the 2025 International Roadcheck, and once again, the data shows that compliance comes down to two things: human compliance and equipment integrity.

Over three days in May, enforcement personnel across North America conducted over 56,000 inspections. The numbers are staggering: 10,148 commercial vehicles and 3,342 drivers were placed out-of-service (OOS). The vehicle OOS rate was 18.1%, and the driver OOS rate was 5.9%.

If you want to keep your fleet in the compliant 81.9% (vehicles) and 94.1% (drivers), you need solutions that take things off your team’s plate, not add to it.

1. The Driver Problem: Reducing the Mental Load

This year, the CVSA placed a special emphasis on False Records of Duty Status (RODS), a critical driver violation. The results confirmed it is a pervasive issue: 332 drivers were placed OOS for False Logs/RODS, accounting for 10% of all driver OOS violations.

False logs are a symptom of a deeper problem: driver mental fatigue and overload.

The modern driver has an overwhelming number of duties, from performing a precise pre-trip inspection to constantly managing their digital logbook. When drivers are forced to hunt for parking or worry about their battery health, they are mentally distracted, leading to mistakes in their documentation. They falsify logs, not always out of malice, but often because they are struggling to reconcile a difficult, non-compliant reality with the documentation requirement.

The Solution: Idle Smart Automates Comfort and Compliance

The strongest way to eliminate False Log violations is to use technology to reduce the driver’s overall compliance burden.

Idle Smart reduces the mental burden of driving by automatically managing idling, cabin temperature, and battery health for the driver. Automating the responsibility of balancing costs and efficiency with comfort lets your drivers focus on the most critical aspects of their job, keeping them comfortable and well-rested without racking up idle fuel costs. Plus, with protection against battery drain and fuel gelling, your drivers can stop worrying if the truck will start in the morning.

Simplified Process: While many OEM systems claim to manage idling, they often require multi-step processes to activate, and can be accidentally tripped/turned off by the driver opening the door. Idle Smart makes it easy to activate, and hard to mess up; idling, battery protection, and fuel gelling run automatically, and to activate Cabin Comfort, drivers only need to press “Turn On” on their display.
Compliant Rest: By automating cab environment management, you ensure drivers get uninterrupted, compliant rest, reducing the need to make stressful logbook adjustments or log off-duty time while still actively managing their truck.
Focus on the Road: When drivers know comfort and battery life are handled, they can focus their mental energy on compliance duties that only they can perform, like cargo securement and checking their ELD.

2. The Vehicle Problem: Getting Proactive with the Top Killer

While the focus was on tires this year, the primary issue was brake systems.

The CVSA reported that brakes were the undisputed top vehicle violation:

Combined, 5,561 brake-related OOS violations were issued.
This accounted for a massive 41.1% of all vehicle OOS violations.
Brake Systems and 20% Defective Brakes were the top two OOS categories.

These numbers prove that relying solely on a driver’s visual pre-trip is insufficient to keep your vehicle OOS rate below the 18.1% national average.

The Solution: SmartInsights Adds Visibility Where it Matters Most

While your Idle Smart system manages power draw, its Predictive Maintenance tool, SmartInsights, provides essential visibility into your vehicle’s most failure-prone systems, notifying you about potential issues before they escalate into breakdowns (and so you can address them before they become CVSA violations):

Brake Health: SmartInsights can surface alerts for critical problems like Anti-Lock Braking (ABS) Faults. These are hidden electrical or system issues that a driver cannot find on a standard walk-around but will trigger a Level 1 OOS violation.

By coupling the driver-forward solutions like Idle Smart with predictive maintenance tools like SmartInsights, you arm your fleet with the tools to tackle both the #1 driver problem (HOS/False Logs) and the #1 vehicle problem (Brakes). It’s the only way to reliably beat the Roadcheck odds every year.

Want to talk about how Idle Smart can help you pass next year’s road check with flying colors?

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5 Ways Canadian Fleets Master Winter with Automatic Idling

For Canadian fleets, winter is a threat to profitability. Learn...

For heavy-duty Canadian fleets, winter isn’t just an inconvenience; it’s a recurring threat to profitability. From batteries failing in sub-zero temperatures to diesel fuel gelling and engines refusing to turn over, the risks are everywhere. These incidents aren’t minor hiccups; they are major operational failures that lead to lost revenue and endless headaches for leaders like you.

The question isn’t whether your trucks will face these challenges, but what you’re doing to prepare for them. The smartest fleets are building a plan for operational survival that puts technology to work for them, even on the coldest days of the year.

Here are five ways Idle Smart is helping Canadian fleets master the winter and protect their bottom line.

1. Protection Against the Dreaded No-Start

Getting an emergency call because of a truck failing to start on a frigid morning keeps fleet executives up at night; that’s why Idle Smart is engineered to minimize the risk of cold starts.

How it works: Our system continuously monitors battery voltage and engine coolant temperatures. When either drops below a pre-set threshold, the system automatically and safely starts the engine to recharge the batteries and warm the coolant.
The benefit: This automation ensures your fleet is always ready to roll, eliminating the need for costly roadside assistance calls and preventing hours of lost productivity. Idle Smart helps you avoid the financial hit of a no-start, driver frustration, and the logistical nightmare of rescheduling a critical load.

2. A Maintenance-Free Answer to Fuel Gelling

Diesel fuel gelling is a common problem in extreme cold, as the wax in the fuel begins to crystallize, clogging fuel filters and lines. It can stop a truck dead in its tracks. While many fleets rely on fuel additives or manual idling to combat this, Idle Smart offers an intelligent, hands-free solution. The system runs the engine long enough to warm the fuel lines and prevent gelling. Keeping fuel lines clear is especially valuable when drivers are on their rest periods for a day or more; Idle Smart will protect the fuel lines from gelling even if drivers are away from their trucks, ensuring your trucks can start and run reliably every time, regardless of the temperature.

3. Extending Battery Life in Harsh Conditions

Cold weather is brutal on batteries, draining them of power and reducing their lifespan. Idle Smart helps extend their lifespan by keeping them in an optimal state of charge. By automatically engaging the engine to top off the charge, the system prevents the deep-discharge cycles that prematurely wear out batteries. Most systems monitor a battery’s health using a percentage, which is an estimate that can be thrown off by firmware and battery degradation. We provide a more reliable measure by monitoring the actual battery voltage, which is a direct physical property that more accurately reflects the health and charge of your batteries.

Maintenance leaders know that every dollar saved on battery replacements goes directly back to the bottom line. It’s a small change with a massive impact. As one fleet leader put it, “Between the fuel savings and the added battery protection, it’s honestly a no-brainer. The system pays for itself many times over.”

4. A Smarter Alternative to APUs and Excessive Idling

You don’t have to settle for the limitations of outdated technology. APUs can provide comfort and power, but they come with a steep price tag, significant weight, and a constant need for maintenance and repairs. Manual idling, while common, is an inefficient and expensive way to keep a truck warm. With Idle Smart, you get a maintenance-free, lightweight system that installs in about an hour and provides instant fuel savings. Plus, unlike APUs that require replacement every 3-5 years, Idle Smart lasts for the life of your truck.

The system’s intelligent engine control keeps the cabin at a comfortable temperature without excessive idling or incurring high costs. Using maintenance-free solutions like Idle Smart frees up technicians from constant “firefighting,” which is critical as the industry is faced with an ongoing technician shortage. In a demanding market, tools that drive this kind of efficiency are a competitive advantage that keeps the most talented technicians on your team.

5. Data and Control from the Comfort of Your Office

Knowledge is power, especially when it comes to managing a fleet in the winter. Most APUs don’t provide data, and those that do often have a fairly limited scope. Our SmartPortal platform gives you visibility into your entire fleet’s idling behavior, regardless of OEM; it provides unprecedented control over your fleet’s efficiency right from your desk. You can see how the system is working and adjust parameters for a single truck, a group, or your whole fleet to maximize your fuel efficiency. See who is using the system most effectively, establish coaching opportunities, track your fleet’s fuel savings, and get actionable insights into potential maintenance issues.

Winter Is Coming. Are You Ready?

Winter will always be a challenge for Canadian fleets, but the right technology can transform it from a period of operational stress into a time of predictable efficiency.

Ready to winterize your fleet’s operations and protect your bottom line?

Schedule a no-risk consultation to learn how Idle Smart can prepare your fleet for anything Mother Nature throws at it.

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Extreme Weather Trucking Solutions: A Guide to Managing Fall Temperature Swings

Temperature swings threaten your fleet's uptime and profits. Learn how...

The Fall Dilemma

The morning air is crisp and cool, but by the afternoon, you’re sweating. This is a common experience during the fall and spring, but for a fleet, these drastic temperature swings are a silent threat. While your fleet might be prepared for the peak of summer or the depths of winter, the unpredictable shifts in between can create unique challenges that lead to unexpected downtime, maintenance issues, and driver discomfort.

Ignoring these temperature swings means leaving your assets and drivers vulnerable. The good news is, there’s a better way to manage seasonal temperature volatility. A solution that handles these changes automatically, protecting your fleet’s equipment and the people who drive it.

The Strain of a Shifting Climate

Temperature swings don’t just feel uncomfortable; they put stress on a truck’s critical systems and its driver.

Engine & Fuel: The rapid change from warm to cold weather can lead to fuel gelling, compromise fuel filters, and cause engine stalls or no-starts that leave your drivers stranded. Beyond that, the stress of frequent thermal shifts can accelerate engine wear, leading to unplanned service needs and a shorter component lifespan.
Batteries: Temperature swings are a primary cause of battery failure. While heat can degrade a battery’s internal components, cold weather robs it of its power output. This dual challenge increases the risk of a no-start situation, which is a major contributor to roadside delays and towing expenses.
Driver & Comfort: When a driver’s sleep is disrupted by uncomfortable cabin temperatures, it can affect their fatigue levels, job satisfaction, and overall morale. For fleet executives, this is a critical operational risk that can affect safety records, on-time performance, and, most importantly, driver retention in a highly competitive market.

The Old Way vs. The Smart Way

Traditional methods like idling all night or using simple bunk heaters only address some of these issues, often leading to wasted fuel and increased maintenance costs. Idle Smart offers a comprehensive solution for managing the effects of temperature swings.

Protect your engine and batteries: The system monitors both coolant and battery voltage, automatically starting the engine when needed to prevent cold-start failures, fuel gelling, and no-start situations. It keeps your trucks ready to roll without relying on manual intervention.
Maintain driver comfort automatically: Idle Smart maintains a comfortable, pre-set temperature range in the sleeper cab. This ensures drivers get uninterrupted rest without having to manually adjust settings or idle unnecessarily.
Reduce wear and tear: By running the engine only when necessary, the system minimizes the strain on your engine and reduces the wear and tear associated with excessive idling. This can extend the life of your equipment and lower long-term maintenance costs.

How to Prepare Your Fleet for What’s Next

Taking control of your fleet’s idle management with Idle Smart is a proactive move that pays off in every season. Here’s how you can prepare for temperature swings and all the other unpredictable challenges the road throws at you.

Get the Data.

You can’t fix what you don’t measure, and most systems don’t give you an accurate picture of your fleet’s idle activity. Idle Smart’s platform, the SmartPortal, provides insights into idle time, battery health, and engine starts, giving you a complete picture of where your fleet is vulnerable. With this data, you can see exactly where costs are coming from and make informed decisions.

Idle Smart System: Managing Temperature Swings

Automate your protection.

Systems that require driver intervention add to their workload and stress, and increase the likelihood of human error or missed steps. Idle Smart’s automated system manages idling, battery voltage, and climate control, reducing the risk of human error and ensuring consistent performance across your fleet. Handling these tasks automatically keeps your drivers on the road and helps improve idling more consistently across your fleet.

Align your team with a clear strategy.

Onboarding and adoption are key to successfully implementing new technology. Idle Smart invests in your success from day one with dedicated Customer Success Managers who provide virtual installation assistance, ROI-focused onboarding, and extensive support for everyone in your fleet, from drivers to executives. Plus, get “Train the Trainer” sessions to educate technicians about the system, so they understand how it works and can teach drivers to use it to improve their comfort and safety.

A Proactive Approach for Any Season

The unpredictable nature of temperature swings doesn’t have to be a threat to your fleet. By adding critical tools to your tech stack and shifting to proactive maintenance, you can protect your assets, cut costs, and improve driver satisfaction. Idle Smart helps you reduce downtime, lower maintenance costs, and boost fuel efficiency, giving you a smarter way to manage your fleet in any season.

Schedule a no-risk consultation to see how Idle Smart can help you weather the seasonal changes headed your way.

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