MATS, LOUISVILLE -- An easier way to check regulated air pressure at the control box is now available on the Meritor Tire Inflation System (MTIS) by P.S.I. The control box check point option was previously available on a limited basis, but now can be included with any MTIS purchased for new trailer installations or retrofits.


With the new feature, mechanics and drivers can check air pressure without shutting off the system and disconnecting the supply line from the control box. Control box air pressure is set slightly higher than customers’ specified tire pressure so the system delivers the desired pressure to the tires after passing the check valves. 


“Fleets want a simpler way to change their desired system pressure or validate their current setting,” said Charlie LaFuente, P.S.I.’s engineer and quality control manager.


MTIS by P.S.I. is an automatic system that immediately provides air pressure to any trailer tire should the pressure fall below the desired setting, without action by drivers or waiting for attention from mechanics, he said.


By keeping tires properly inflated, MTIS by P.S.I. improves tire maintenance management, trailer uptime and bottom-line ROI and reduces CSA (compliance, safety, accountability) violations. The simple and reliable design can be installed as new or as a field retrofit on any type of trailer.


Systems are now in use on van, liquid and dry bulk tank, logger, flat bed, chassis, livestock, platform, drop frame, dump, deep drop, pup, reefer, auto transporter and military.


Proper tire inflation boosts tire life, increases fuel efficiency and safety, maximizes recap potential and keeps trailers on the road, experts have long pointed out.



A patented ThermAlert option warns drivers of excessive wheel-end heat, which helps avoid trailer fires and damage to the undercarriage. Currently, more than 50% of P.S.I.’s production is specified with ThermAlert. 


MTIS by P.S.I. is compatible with the Meritor Wabco PLC Display for tractor-trailer communications as well as other telematic devices. Meritor trailer systems and components are backed by Meritor’s competitive warranty, global services and support. 


Pressure Systems International markets and sells its products in North America through Meritor as the MTIS by P.S.I. P.S.I. has also opened markets in 40 countries and is currently exporting to China, Europe, South America, Africa and Australia. 

More information about Pressure Systems International is at