TORONTO, Ont. — The Ontario Trucking Association has applauded the Ontario Ministry of Transportation’s first big step to allow the use of tractors with longer wheelbases. The province has passed a regulatory amendment, which will take effect July 1, to allow longer wheelbase tractors for single, tandem and tridem semi-trailer configurations.

The change is designed to accommodate environmental devices and add-ons, while meeting or exceeding MTO’s turning performance standards and all other HTA dimensional criteria.

Under the change, the maximum allowable tractor wheelbase will increase from 6.2 m (244 in.) to 7.2 m (282 in.) for vehicles classed as SPIF1 (Safe, Productive and Infrastructure Friendly) Designated Tractor-Trailer Combinations (i.e., single, tandem and tridem tractor/fixed axle semi-trailer configurations).

To accommodate for the longer tractors, MTO is using a formula which reduces trailer wheelbase as tractor wheelbase increases, allowing the configuration to negotiate turns the same as any other vehicle. Currently, all other Canadian provinces allow a longer wheelbase tractor, although all but one (Nova Scotia) only do so by special permit. (There is no maximum tractor wheelbase requirement in the US).

The OTA says it had been seeking changes to the maximum wheelbase restrictions in order to allow the industry the flexibility to accommodate recently introduced truck engine technologies like particulate traps, urea tanks, selective catalytic reduction canisters, diesel exhaust fluid tanks and other devices like auxiliary power units (APUs) to meet emission standards aimed at reducing greenhouse gases.

The change was welcomed by OTA. “The configurations MTO has moved forward on represent approximately 85% of the trailer fleet operating in Ontario,” said OTA president David Bradley.

OTA has already begun work with MTO to determine the feasibility of allowing longer wheelbase tractors on other SPIF configurations including tri-axles, quad-axles, five, six-axle and B-train configurations.

Together these components can occupy up to two metres (80″) of frame rail space, or half of the area between steer and drive axles currently available to carriers on a 6.2-metre wheelbase tractor. This impinges on space typically reserved for fuel tanks, air supply tanks, batteries and other equipment and makes spec’ing a vehicle very difficult, according to OTA officials, who noted that spec’ing APUs on tractors with a sleeper berth is a particular challenge. Emerging technologies like hybrids and LNG vehicles may also create pressure on trucks’ frame rail space, the OTA said.

To view the official MTO regulatory amendment, click here.