Agricultural tractor on road with implementChanges in ag vehicle braking requirements for North America are being considered.

The standard containing braking requirements for towed and towing agricultural field equipment is in need of updating to keep pace with current machine design and practices.

A small task force of braking system experts from several North American-based equipment manufacturers along with developers and suppliers of vehicle braking systems has been comparing the current requirements in ASAE S365.9 to the demands current equipment and practices are placing on braking systems as well as requirements from other regions of the world.

The review of the dated North American braking standard will take the next step towards a thorough revision when manufacturers meet in mid-June. The industry-driven review has progressed to a point where a broader coalition, including manufacturers of brake components, self-propelled, towed and towing equipment, will meet to review ASAE S365.9 as it applies to agricultural equipment currently being marketed. 

The group recognizes that increases in equipment speed, weight and size along with greater congestion of U.S. roadways are placing more demands on the performance and design of agricultural equipment braking systems.

Still a Long Way to Go

While much work has already been completed, there is still a long way to go and many more voices to take into consideration. Invitations have been extended to a broad base of interested parties in both the U.S. and Canada. The upcoming meeting will bring new attendees up-to-date on the current status, needs and timelines to enhance existing standards and, where possible, establish consistency with other regional standards and regulations, thereby improving manufacturing efficiencies.

Topics to discuss include means to resolve the concerns over the current ASAE S365.9 standard which:

  • Has no provision to allow towing of a lightweight towed ag vehicle without brakes at speeds exceeding 32kph (20 mph)
  • Has no distinction between commodity trailers with variable transport loads and implements with fixed transport loads
  • Does not address how the brake system interfaces between towing vehicle and the towed vehicle
  • Has no provisions to warn an operator that the brake system has failed
  • Does not clearly address requirements for combination braking systems (hydrostatic & friction brakes)
  • Increases complexity for manufacturers and users due to the misalignment with other standards around the world.

Once agreement has been achieved, the discussions will move to the formal ASABE standardization process.

For More Information

For more information, contact Michael Pankonin, AEM senior director, technical and safety services (, tel: 414-298-4128).