The Benefits of Predictive Maintenance

Real-time technologies help reduce over-maintenance and more

The entire area of commercial vehicle maintenance has evolved over the past six decades, and that’s a positive move for the industry and its vehicles. Properly caring for trucks, tractors and trailers has advanced from a “just fix it” mindset, to technicians keeping a watchful eye for likely trouble spots or failure-likely components and systems, to the formal preventive maintenance, to today’s more popular predictive maintenance.

Traditionally, fleet maintenance managers and industry suppliers have used reliability statistics from standardized testing to structure preventive maintenance intervals and schedule fluid or component replacements and tire rotations.

Going forward, real-time technologies and actual fleet data are replacing these old methods. This will significantly reduce maintenance costs, improve vehicle performance, improve vehicle emissions compliance and increase vehicle time in-service (uptime).


Interestingly, one common element crosses all the evolutionary steps: solutions. From the most elementary stage of “just fix it,” to the data-driven solutions of today, there has been tremendous improvement, plus a steady progression towards preventive maintenance.

Nearly a decade ago, a Technology & Maintenance Council technical session from March 2003 reported on the Sound Science for Fleet Prognostics. The exploratory paper was produced as a framework for things the industry should be watching.

Nine years later, the main value of predictive maintenance remains to allow convenient scheduling of corrective maintenance and to prevent unexpected equipment failures. This approach offers cost savings over routine or time-based preventive maintenance.

Vehicles and respective owners have benefitted from the ability to transport more freight and goods more efficiently to consumers and businesses across North America.

The key has been having the right information at the right time. By knowing which piece of equipment needs maintenance, the maintenance work can be better planned for parts and people resources. Plus, what would have been “unplanned stops” are transformed to shorter and fewer planned stops, thus increasing plant availability.

Other values are increased equipment lifetime, increased shop safety, fewer accidents with negative impact on environment and optimized parts inventory and usage.


All on-highway trucks and tractors now have a minimum of four computers, and most have as many as six. A recent examination of a late-model tractor revealed a separate onboard computer for each of these systems: engine, exhaust, cab, antilock braking system, driver side airbag, automated manual transmission, in-dash driver center and a management/driver log system.

These onboard computers are known as an engine control or electronic control module (ECM) or electronic control unit (ECU). Along with running the operating systems for the component they were designed with, these computers also monitor sensors for variances that are outside of their normal operating parameters.

These variances, called fault codes, are logged and stored into the system’s memory as they occur. When an inactive fault code become active or severe, then a dash-mounted malfunction indicator lamp (MIL) is turned on to warn the driver about system malfunctions.


As vehicles get connected to the Internet via telematic systems, more and more maintenance managers are collecting performance data into their maintenance systems and receiving e-mail messages from their vehicles. The e-mail messages let managers know about both active and inactive fault codes as they occur.

The e-mail messages can also include GPS location information, ambient temperature and other critical information that can be vital to help diagnose the root cause of the fault code. With such information, a fleet maintenance manager can direct the driver to a repair location if component failure may be immediate, or order parts and have them ready if the fault codes are inactive and the vehicle can safely and reliably run back to the home base location.

This content continues onto the next page...

We Recommend