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Meritor Tire Inflation Systems

We are pleased to announce the addition of the Meritor MTIS Tire Inflation System with ThermAlert to our new and future trailer additions. We want to provide you (our driver) with tools and equipment to keep you on the road safely. With this new addition we would like to provide a brief overview of the system and what to expect.

Features and Benefits of the Meritor Tire Inflation System (MTIS)

  • Extended tire life: Underinflation results in increased and uneven wear, which drives up the frequency of tire replacement. By maintaining tire pressure at all times, MTIS by P.S.I. can extend tire life by 10 percent.
  • Increased fuel economy: MTIS by P.S.I. increases fuel economy by an average of 1.4 percent, according to a Federal Motor Carrier Safety Administration (FMCSA) study. 
  • Improved safety: MTIS by P.S.I. significantly reduces the risk of tire blowouts and the potentially costly and dangerous consequences. Moreover, the ThermALERT™ wheel-end heat sensing technology option helps prevent wheel-end failures from heat build-up. 
  • Fewer Breakdowns: Tires are the top reason for costly service calls, many of which can be attributed to simple underinflation. MTIS by P.S.I. virtually eliminates those calls.   


·        Features & Benefits of ThermALERT:

  • If the temperature of the wheel-end elevates into a dangerous operating zone, the eutectic screw installed in the press plug will melt causing pressurized air to vent through the hub cap tee vent.   
  • The indicator light will come ON, there will be an audible sound at the wheel-end as air vents through the hub cap tee vent.  
  • Helps alert drivers to stop for repairs before serious damage occurs due to elevated wheel-end temperatures.
  • Helps reduce downtime, risk and operating cost. 
  • Gives the opportunity to inspect and repair components that caused the wheel-end to exceed normal operating temperatures before the trailer is put back into service to prevent serious personal injury and damage to the trailer components.


Check that the tractor air has reached maximum air supply (125-130psi) and the 7 way is connected to the trailer

The indicator light located on the roadside front corner of the trailer should be off within 10 minutes of the trailer being supplied air from the tractor. If the light stays on longer than 10 minutes, notify dispatch and maintenance that there is a tire problem.  

Check the wheel ends to verify that hoses are connected to the thru tee assembly and to the valve stem. If you hear an audible leak notify dispatch and maintenance that there is a problem.

During your pre-service inspection you will find that your trailer is equipped with a Thermalert decal and warning light.  Two conditions will cause this light to illuminate. The first is an under inflated tire, and the second is the event of an abnormally high wheel end temperature.

During Travel Service

If the indicator light comes on during your travels, find a safe place to pull over and inspect your tires and wheel ends. Try and determine which tire is damaged or low before calling for breakdown assistance. If you hear audible air coming from the hubcap relief valve (the shield on the thru tee) the wheel end may be running at an abnormal high temperature. Contact your dispatch and breakdown to have the appropriate repair made before safely resuming your trip.



if you have any questions or concerns about this system please do not hesitate to reach out to us through your local Fleet Manager, on Facebook, using the contact us form found here.

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