Leveraging Tire Pressure Monitoring Systems for Tire Health

On paper, tires might seem like a relatively insignificant cost for most standard fleet assets. Compared to parts that are notoriously expensive to replace (like engines and transmission systems), equipping a vehicle with a new set of tires is rather affordable, both in terms of the tires themselves and the labor needed to install them. As a result, many fleets might not feel the need to monitor the condition of their tires beyond their usual vehicle inspections.

But while tires may not be a particularly notable expense themselves, the things they influence have a profound impact on any fleet’s bottom line. For example, improperly inflated tires can have a noticeable impact on a vehicle’s fuel economy, and given how much fleets spend on fuel, that reduction in efficiency can quickly add up to thousands of dollars needlessly wasted. Additionally, delays from a flat tire at the wrong moment can throw work schedules into disarray, resulting in lost productivity, customer frustration and even damage to an organization’s reputation.

Fortunately, tire pressure monitoring systems (TPMSs) allows fleets to minimize tire-related issues, resulting in less unplanned downtime and improved TCO.

How does a tire pressure monitoring system work

At their most basic, TPMSs use either physical sensors or software to gauge tire pressure and alert drivers when a tire falls out of a designated pressure range via a dashboard light. More sophisticated TPMSs can also monitor tire temperature and detect leaks and are capable of notifying select fleet personnel of possible issues via text or email.

In terms of technology, there are two kinds of TPMS—indirect and direct.

Indirect TPMSs

Instead of relying on dedicated tire sensors, indirect TPMSs typically use a combination of software and a vehicle’s anti-lock brake system to keep tabs on tire conditions. By measuring the revolutions per minute (RPM) of each of its tires, a vehicle’s on-board computer can determine their size in relation to each other. When a tire’s RPM increases out of step with its counterparts, that’s often a sign of under-inflation. Upon detecting such an RPM change, an indirect TPMS will notify its driver of the possible issue.

Compared to direct TPMSs, indirect TPMSs are more affordable because they don’t require any additional hardware to function. A lack of tire sensors eliminates upfront procurement costs as well as labor costs related to installing, programming and maintaining them. Additionally, because indirect TPMSs are solely dependent on software and equipment calibrated by the vehicle manufacturer, they don’t require as much fine-tuning as direct TPMSs. OEM-set configurations are typically good enough for most use cases.

But in terms of reading accuracy, indirect TPMSs can be thrown off by a number of different factors. For instance, equipping a vehicle with tires bigger or smaller than what it originally had can result in occasional false positives. What’s more, in situations where a vehicles’ tires wear down unevenly, it becomes harder for its on-board computer to make comparisons that establish a properly inflated baseline. In such scenarios, it’s possible for under-inflated tires to go undetected for significant periods of time. And finally, indirect TPMSs must be reset after properly inflating every tire and after tire rotations. While the resetting process doesn’t take particularly long, it does add another step to common tire maintenance procedures.

Direct TPMSs

For actual tire pressure readings, fleets should turn to direct TPMSs. Direct TPMSs use physical sensors embedded within tires or attached to tire valve stems. These specialized, battery-powered sensors constantly measure air pressure within the wheel they are associated with to provide precise pounds per square inch (PSI) readings. Via radio waves, these readings are then transmitted to an in-cab receiver.

This straightforward approach enables direct TPMSs to achieve greater accuracy than their indirect counterparts. Additionally, direct TPMSs are less fussy when it comes to tire rotations and replacements. While they still require resynchronization after their tires receive service, the process of getting them up and running again is generally less cumbersome than with indirect TPMSs. Finally, the sensors that direct TPMSs enable additional readings like tire temperature and leak detection. Indirect TPMSs simply lack the ability to monitor for such conditions.

But compared to indirect TPMSs, direct TPMSs are more expensive to operate. TPMS sensors generally cost between $50 and $200 per unit. Multiply that by every wheel of every vehicle in your fleet and it’s easy to see how that cost adds up. Additionally, the batteries that power TPMS sensors don’t last forever. Fleets should expect their sensors’ batteries to expire approximately a decade after purchase. These batteries cannot be replaced, so fleets have no choice but to purchase a new batch of sensors every ten years or so. What’s more, embedded sensors can be damaged during wheel mounting and demounting. Fleets should instruct their technicians to take care when performing such actions to avoid accidentally dislodging any sensors.

TPMSs and fleet management systems

While TPMSs provide lots of utility on their own, they become even more beneficial to fleets when paired with fleet management systems (FMSs). Through integrations that automatically feed sensor data to FMSs in real time, organizations can passively monitor the health of every tire of every vehicle in their fleet from anywhere with an internet connection.

Importantly, TPMS-to-FMS integrations also can alert fleet managers and other stakeholders when a tire issue is detected (instead of just the driver of the associated vehicle). This extra layer of visibility helps ensure tires in need of service don’t go ignored. Additionally, it’s easier for tire issues to be converted into work orders when TPMSs and FMSs are interlinked. Instead of having to create a work order from scratch, many FMSs allow issues to be automatically converted with a single click.

What’s more, FMSs make staying on top of tire maintenance far more manageable via checklists and automatic reminders. Checklists provide your technicians with an easy way to keep track of the service actions they need to perform. By simply marking off tasks (like tire tread inspections) as they perform them, fleet managers can track their progress in real time while also reducing the likelihood of any step being forgotten. As for automatic reminders, FMSs can send notification alerts when one of your maintenance schedules has work approaching soon. These helpful heads-ups give your technicians a greater sense of what their workload is like, enabling them to balance their time more effectively.

Finally, FMSs can also make addressing more serious tire issues easier by streamlining communications between your organization and fleet repair shops. Instead of having to go back-and-forth with countless emails and phone calls, FMSs with partnered repair shops enable organizations to approve work (down to the individual line item level) entirely through their computer or smart device. In addition to saving you time, this setup helps minimize the risk of unexpected charges by providing complete visibility over every action repair shops perform.

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By investing in TPMSs, fleets can more effectively address the needs of their tires and, in turn, meaningfully improve the fuel economy, reliability and safety of their vehicles. When paired with fleet management software, TPMSs give fleets even more visibility over a vital aspect of their operations.