TORONTO —The Ontario Ministry of Transportation (MTO) wants to allow longer tractor wheelbases for a specified group of heavy truck configurations. The change, MTO said, would accommodate environmental devices and add-ons that are essential in reducing greenhouse gases.

The proposed change would increase the maximum allowable tractor wheelbase from 6.2 m (244 in.) to 7.2 m (282 in.) for vehicles classed as SPIF 1 (Safety, Productivity and Infrastructure Friendly) Designated Tractor-Trailer Combinations — single, tandem and tridem tractor/fixed axle semi-trailer configurations.

The Ontario Trucking Association (OTA) applauded the proposal, saying that they had been seeking changes to the maximum wheelbase restrictions for some time.

It would allow the industry flexibility in accomodating truck engine technologies, OTA pointed out, like particulate traps, urea tanks, selective catalytic reduction canisters and diesel exhaust fluid tanks, to meet emission reduction standards and other devices, such as auxiliary power units (APUs) aimed at reducing greenhouse gases.

"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," OTA said in a press release. "This impinges on space typically reserved for fuel tanks, air supply tanks, batteries and other equipment and makes spec’ing a vehicle very difficult.

Spec’ing APUs on tractors with a sleeper berth is a particular challenge, OTA noted. Emerging technologies like hybrids and LNG vehicles may also create pressures on frame rail space on trucks.

OTA President David Bradley said the MTO proposal is a good first start. He said that by going the regulatory route, costly and administratively burdensome permits can be avoided.

But, he said, they will be seeking an expansion to the list of configurations contained in the proposal to allow longer wheelbases on other SPIF configurations that can meet or exceed the same turning performance criteria as those already listed, including the SPIF tri-axle, quad –axle, five and six-axle configurations.

“The additional vehicles we think should also be included are consistent with the intent of the proposed regulation," Bradley explained, "and share the same characteristics consistent with criteria used to determine those vehicles that should be approved for longer wheelbases."

The proposed amendments are subject to the statutory 45 day comment period, OTA said, but could come into effect as early as this summer.