FMVSS 138

Tire Pressure Monitoring Systems

This Standard applies to MPVs, trucks and buses with a GVWR of 10,000 lbs. (4,536 kg) or less, except those vehicles with dual wheels on an axle. It specifies performance requirements for tire pressure monitoring systems to prevent significant under-inflation of tires.

Applicability:

Trucks & MPVs 10,000 GVWR or Less Yes
Trucks More than 10,000 GVWR No 
Buses 10,000 GVWR or Less Yes
Buses More than 10,000 GVWR No 
Trailers No 

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