Tri-Axle Trucks

Res #: 13-06M
Number: 13
Year: 2006
Midterm: Yes
Expired: Yes
Responses Received: No
Departments: Saskatchewan Highways & Transportation

Resolution No. 13-06M  


BE IT RESOLVED, that solid-frame trucks with a single axle at the front and triple axles at the back be permitted on Saskatchewan roads.


Response from Honourable Eldon Lautermilch, MInister of Highways and Transportation:


Regarding Resolution No. 13-06M Tri-Axle Trucks, the Department of Highways and Transportation (DHT) supports the use of tridem drive straight trucks and is proposing an amendment to The Vehicle Weight and Dimension Regulations, 1999, that would permit solid-frame trucks with a single axle at the front and triple axles at the back on Saskatchewan roads.


Tridem drive trucks with permanently mounted equipment and non-divisible loads have been operating in this province under permit for several years.  The use of these trucks results in efficiency gains from increased payload, allows increased equipment size, and provides extra traction from the tridem drive.  The weights allowed on a tridem axle group are controlled primarily by short span timber bridges.


Research has shown that for a given load, as the axle spread increases, the impact to short span wood bridges decreases. This sensitivity to loading is the basis for the allowable weights of tridem axle groups based on axle spread.  For this reason, the proposed weight allowed on a tridem drive axle group hauling divisible loads is capped at 20 000 kg on municipal roads and secondary weight highways, and 22 000 kg on primary weight highways.  If there any further questions about this matter please feel free to contact Andrew Cipywnyk, Manager, Trucking Policy at
(306) 787-6998 in