terms of vehicle characteristics operating across and along the western border. Examples are lift axles, wide-base tires, and excessively long drawbars between trailers and between trucks and trailers.
Split tandems are used in semitrailers in the western border States. They allow, where permitted, operating five-axle tractor-semitrailers at a GVW of 86,000 pounds and more flexibility in loading at lower GVWs. The 10-foot spread of these axles is effectively prohibited by the Canadian RTAC regulations and by the western Canadian provinces. Ontario and Quebec permit the use of split tandems.
Tridem- and quadrem-axle arrangements are used across and along the western border and often incorporate lift axles and wide-base tires. One major trailer manufacturer indicates that tridems are becoming the axle arrangement of choice for many carriers in the northwest region.
Differences in tire load limits among the ten western jurisdictions have no significant effect on western border trucking. Canadian regulations generally discourage the use of wide- base tires by placing limits on the total allowable load per tire. In certain western border States, on the other hand, the tire load limit of 600 pounds per inch of width with no limit on the total allowable load per tire tend to encourage the use of wide-base tires.
Canada's steering axle limit of 5,500 kilograms causes problems for U.S. trucks at certain crossings. U.S. vehicles entering Manitoba from I-29 can come in with a steering axle load of as much as 6,000 kilograms, and are required to move their fifth wheel to comply with the 5,500 kilograms requirement.
Western border States (except Minnesota) permit 14-foot high vehicles. This is 6 inches more than allowed in the western Provinces. Fourteen-foot high vans are common throughout the western United States particularly with specialized truckload carriers. These vehicles are being permitted to operate into at least one western Province. Alberta has proposed 14 feet as the height limit for the Canamex Corridor (see Appendix C), an international trade corridor originally proposed by Alberta that extends from Alberta generally along I-15 to California and Mexico.
RTAC regulations require the wheelbase of a tractor to be within the range of 3.0 to 6.2 meters (118 inches to 244 inches). Some U.S. carriers wish to operate tractors having shorter (2.7 meters--106 inches) or longer wheelbases (6.7 meters--265 inches) into the western Provinces. Some Provinces prohibit use of these non-RTAC tractors, others allow their use under special permits, while still others ignore their non-compliance.