Kenworth adds Bendix CVS SmarTire tire pressure monitoring system

Kenworth Truck Company has announced the addition of the SmarTire Tire Pressure Monitoring System (TPMS) from Bendix CVS as an option on select Class 8 trucks.

The SmarTire technology monitors the pressure and temperature of each tire on a commercial vehicle to provide real-time tire status information to the driver. The technology is designed to warn the driver of tire-related problems, such as low pressure and high temperatures, before they become serious issues.

The system reads pressure and temperature information from inside the tire and communicates wirelessly to an on-board receiver.

"With so much riding on their truck tires, fleets are finding that they need to be more proactive in addressing tire inflation issues," said Erik Johnson, Kenworth on-highway marketing manager.

"By equipping their trucks with the SmarTire Tire Pressure Monitoring System, truck and fleet operators can help avoid fuel mileage penalties, large bills for roadside assistance and penalties during roadside inspections. They can also gain more tire life, and reduce expenses that for many truck operators are second only to fuel costs."



According to Bendix, a tire that is underinflated by as little as 10 percent can result in a 1.5 percent drop in fuel economy, which may increase fuel spending by up to $1,000 per year for a single truck.

Underinflation by 20 percent results in a 30 percent reduction in tire life.

A tire failure on the road due to improper tire inflation can also rack up large roadside assistance charges, depending on when and where they occur.

SmarTire's in-vehicle display will be incorporated as a gauge in the Kenworth truck dash. It will provide information including actual tire pressure tire and temperature for each wheel location, along with a deviation value which show the amount of over or underinflation from the tires' cold inflation pressure (CIP). 

This deviation value provides the user a deviation from target pressure, regardless of tire temperature, an important gauge because tire pressure rises when a tire's temperature increases from use or outside conditions.

For drivers and fleets, this means they can accurately maintain their pressures anytime - whether a truck has been sitting idle or has been driving for hundreds of miles.



Monitoring tire pressure has become particularly important as the Federal Motor Carrier Safety Administration's safety enforcement program, Compliance, Safety, Accountability (CSA), places significant importance on tires.

Under CSA, the agency places greater weight on those items that have the highest incidence of accidents associated with them when they're in need of being repaired or replaced. As a result, roadside inspectors would be more likely to sideline trucks with issues involving tires.

A copy of the severity tables and more information about the SMS methodology is available at the agency web site:

Inspectors pay particular attention to tires and deficiencies can rate up to an 8 on the SMS methodology. Underinflated tires and loads that exceed a tire's load limit can rate a 3 according to SMS methodology. Inspectors can also declare a vehicle out-of-service if either of the steer tires has a leak that can be felt or heard or there's 50 percent or less of the tire's maximum PSI of air in the tire.

"Truck fleets and operators can no longer afford to ignore the importance of monitoring tire pressures, particularly with closer scrutiny under CSA and recent increases in tire prices," Johnson said. "SmarTire certainly makes it easier for truck fleets and operators to accomplish that task."

The system will be available as a factory-installed option on the Kenworth T660 and T700 later this year, with plans to offer it on other Kenworth Class 8 trucks soon after.

For more information call or visit a local Kenworth dealer, or visit