SAE J3309_202410

This SAE Recommended Practice defines the system and component functions, measurement metrics, and testing methodologies for evaluating the functionality and performance of tire pressure systems for use on trailers under 26000 pounds GVWR within the known operating environments. This document is applicable to all towed trailers under 26000 pounds GVWR. Examples of towed trailers are recreational vehicle travel trailers and fifth wheels, utility trailers, cargo trailers, livestock trailers, flatbed trailers, boat trailers, and snowmobile trailers. These trailers can be equipped with one, two, or three axles with each axle supporting either two or four tires. These systems are recommended to address all tires in service as originally installed on a trailer by the OEM. This recommended practice can also be applied to external TPMS that also cover tow vehicles and trailers simultaneously. This document will focus on tire pressure systems of the monitoring type. The field of application of this document is trailer tire installed on trailers under 26000 pounds gross vehicle weight rating (GVWR). Normal tire maintenance procedures must be followed regardless of whether a tire pressure monitoring system (TPMS) is used or not. Tire pressure adjustments must be performed even in the absence of any TPMS indication in order to have the optimum tire performance. A TPMS acts only as an aid to the driver detecting pressure and temperature changes during operation. All trademarks used are owned by their respective owners.