The Ontario Highway Traffic Act (HTA) and Regulation 413/05, Vehicle Weights and Dimensions for Safe, Productive, and Infrastructure-Friendly (SPIF) Vehicles, sets out the legislative framework and regulatory requirements for vehicle weights and dimensions measures in the province. Reg. 413/05 sets out a two-tier system of vehicle weights and dimensions. The first tier regulates SPIF compliant vehicles that may operate at the highest weights and dimensions. The lower-tier, non-SPIF (non-compliant) vehicles may also operate but, in some cases, at restricted axle weights and dimensions and at significantly reduced gross weights.
SPIF compliant tractor semitrailers and double-trailer combinations (compliant) are afforded allowable weights as set-out in the corresponding SPIF Schedules within Reg. 413/05, if Qualifying Pre-Conditions and Dimensional Criteria are met.
Non-SPIF tractor semitrailers and double-trailer combinations (non-compliant) are limited to axle weights and dimensions as set out within the HTA including: 14.65 metre (48 foot) long semitrailer length limits, 23 metre (75.5 foot) tractor double-trailer overall length limits, and 18.5 metre (60.7 foot) tractor double-trailer box length limits. These combinations are held to allowable gross weight limits as set out in Tables 32 and 33 of Regulation 413/05.
The 6x2 drivetrain on tandem axle truck-tractors only have one driven axle, as opposed to the more common 6x4 drivetrain, where both axles are driven by engine power. (Note: An axle capable of altering the weight transmitted to the highway is deemed a liftable axle and is considered non-compliant)
|Tandem axles load equalize within 1000 kg, under all conditions of loading.||Tandem axles fail to load equalize within 1000 kg, under all conditions of loading.|
|Tandem axle set does not include a lift axle.||Tandem axle set includes a lift axle.|
|Tandem axles that are not equipped with load shifting (load biasing) traction-control technology.||Tandem axles equipped with load shifting (load biasing) traction-control technology.|
|There are no driver controls within the cab that allow for the altering of weight transmitted to the highway surface between the tandem axles, or give the ability to lift its tires from contact with the highway surface.||There are driver controls within the cab that allow for the altering of weight transmitted to the highway surface between the tandem axles, or give the ability to lift its tires from contact with the highway surface.|