Recent changes to regulations on vehicle weights and dimensions: Safe, Productive and Infrastructure-Friendly vehicles

Amendments to Ontario Regulation 413/05, Vehicle Weights and Dimensions for Safe, Productive and Infrastructure-Friendly (SPIF) Vehicles.

Changes effective July 1, 2019

Effective July 1, 2019, modifications to Ontario Regulation 413/05 will eliminate the special vehicle configuration permits currently required to operate long wheelbase tractors, longer saddlemounts, and trailers equipped with smart lift axles, while empowering industry to use alternative applications of existing technologies and new technologies toward improving operational efficiency:

  • The weight limits for wide base single tires at par weights to the dual tires that they replace;
  • The loading of boats on stinger-steer auto carriers;
  • The operation of long wheelbase tractors on designated tandem tractor semitrailer configurations currently not privy to such an allowance;
  • Extend the overall length of designated saddlemount configurations;
  • Use of smart lift axles on tandem, tridem and quadruple axles on designated tractor semi- and double-trailers; and
  • Clarify the exemption allowing manual controls on designated trucks and tractors to lift a self-steering axle in emergency situations as to be designed to be activated separately and independently of the 4-way flashers.

Frequently-asked questions

Question 1: Why is the government amending Regulation 413/05 related to Vehicle Weights and Dimensions (VWD) – For Safe, Productive, and Infrastructure-Friendly Vehicles (SPIF)?

Answer 1: Regulation 413/05 was the result of a decade long reform project to the vehicle weight and dimension rules which establish a two-tier regulatory system for heavy vehicles in Ontario. SPIF vehicles are allowed higher weights, while non-SPIF vehicles can operate at lower weights. Industry brought forward a request to increase wheelbase allowances on tractors hauling multi-axle semitrailer from 6.2metres to 6.8 metres, to utilize Smart Lift Axles, and to operate longer Saddlemount configurations. While Special Vehicle Configuration permit regimes were established on a temporary basis, amending regulation will remove the need for carriers to acquire these permits so to operate advanced technologies or more productive truck configurations. Further amendments to the regulation include allowing Wide Based Single (WBS) tires on single axles at the same weights as the dual tires that they replace, which will increase fuel mileage and thus decrease truck related emissions for the trucking sector. In addition, the regulation will be amended toward allowing single switch Emergency Lift Axle Override with immediate lifting capabilities on trucks, truck-trailers, tractor semi- and double-trailer configurations.

Question 2: Why is MTO proposing to allow extended wheelbase tractors in combinations?

Answer 2: Over the past few years, Ontario has amended the regulation toward the use of long wheelbase tractors on typical tractor semitrailers with fixed axles and tractor B-train double-trailer combinations, while also harmonizing with all other Canadian jurisdictions. Since that time, the ministry has allowed the use of long wheelbase tractors on all other regulated tractor semitrailer configurations via temporary permit regimes. By accommodating longer wheelbase tractors, carriers engaged in long-haul operations are able to accommodate technologies required to meet air quality and Greenhouse Gas (GHG) emission mandates, allows the use of alternative fuel engine platforms that require additional infrastructure on the truck-tractor, while also providing more comfortable sleeper berths for drivers.

Question 3: Why is MTO reducing the wheelbase allowance of the trailers hauled by the extended wheelbase tractors?

Answer 3: MTO requires that the wheelbase of the trailer hauled by the longer tractors be correspondently reduced. To meet MTO’s road infrastructure standards for cornering, a corresponding change in the wheelbase of the trailer is required. As the tractor wheelbase increases, the trailer wheelbase should decrease, to keep the vehicle within the required turning envelope. A trade-off table, similar to those already in regulation, is being introduced in regulation so to allow these vehicles to operate.

Question 4: Why is MTO allowing longer Saddlemount configurations?

Answer 4: Current HTA limits allow for trucking configurations to operate at up to 27.5 metres, whereby regulation can allow if the vehicles steerability, controllability, and stability can be maintained. The change to allow 3-vehicle saddlemount configurations to operate at 27.5 metres, rather than the current 25.0 metres in regulation, will facilitate the movement of 3 longer wheelbase truck-tractors rather than the current 2. This will reduce costs to the truck manufacturing to sales supply-chain by increasing productivity in the drive-away saddlemount trucking sector.

Question 5: Why is MTO amending single axle weights for wide base single (WBS) tires?

Answer 5: Some configurations in the regulation are currently restricted to 9,000 kg if operating on WBS tires, while duals are afforded up to 10,000 kg. So, to harmonize with Quebec regulation, reduce transportation costs related to fuel, in addition to the associated GHG emissions, the regulation will be amended toward the use of WBS tires at up to 10,000 kg, thus being treated the same as the duals. Although WBS tires are said to increase pavement damage when compared to the dual tires that they replace, impacts to Ontario infrastructure will be almost negligible.

Question 6: Why is MTO amending regulation toward the implementation of an Emergency Lift Axle Override switch?

Answer 6: When Ontario introduced its four-phase overhaul of vehicle weight and dimension regulations, reflected in HTA Regulation 413/05, VWD for SPIF Vehicles, the heavy vehicle configurations within were designed to perform more safely on our highways and within an acceptable amount of space. They are also designed to better protect bridges and pavement from excessive wear while maintaining industry productivity. Technical changes included a move to self-steering axles in place of rigid lift-axles and a requirement that axles automatically load-equalize under all conditions of loading, while removing controls previously available to the driver from within the cab of the truck.

The regulation currently allows the override of the load equalization system while the 4-way hazard indicators are engaged, and while the vehicle is traveling at less than 60 km/h, so that the vehicle can gain tractive effort with the roadway. Essentially, the self-steer axle lifts so to place more weight on the remaining axles of the vehicle to gain traction with the road surface so to that the driver can maintain control of the vehicle. The ministry is amending this allowance toward the use of a single switch that will engage the 4-way flashers, determine if the vehicle is traveling above 60 km/h, and immediately raise the axle. This measure will help drivers maintain better control of their vehicles when it is the correct opportunity to employ this emergency tactic.

Prior changes effective February 5, 2016

The regulatory changes to Ontario Regulation 413/05 (Vehicle Weights and Dimensions – For Safe, Productive, and Infrastructure-Friendly (SPIF) Vehicles) under the Highway Traffic Act modify the following specifications applicable to the dimensions of tractor double-trailers, tractor semitrailers and truck-trailer combinations:

  1. The overall length and tractor wheelbase limits on B-train Double Trailer combinations are extended from 25 metres to 27.5 metres and 6.2 metres to 6.8 metres, respectively.
  2. The allowance for aerodynamic devices at the rear of commercial motor vehicles is extended from 0.61 metres to 1.52 metres.
  3. Minor modifications addressing a technical issue when SPIF compliant trucks are pulling pre-SPIF trailers is addressed in addition to housekeeping changes to correct typographical issues found within the regulation.

The modifications came into force on February 5, 2016.

The first two items were supported by National Task Force (Task Force) on Vehicle Weights and Dimensions (VWD) Policy, under the Council of Ministers of Transportation and Road Safety.


Contact or
1-800-387-7736 (within Ontario) or 1-416-246-7166

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