technical standards document no. 120 tire selection and rims for motor vehicles with a gvwr of more than 4 536 kg revision 2 2 pages available in english and french . notice is hereby given pursuant to section 12 of the motor vehicle safety act mvsa and sections 16 and 17 of the motor vehicle safety regulations mvsr that the department of transport has revised technical standards document tsd no. 120 tire selection and rims for motor vehicles with a gvwr of more than 4 536 kg. revision 2 of tsd no. 120 is effective as of the date of publication of this notice. tsd no. 120 reproduces u.s. federal motor vehicle safety standard no. 120 tire selection and rims for motor vehicles with a gvwr of more than 4 536 kilograms 10 000 pounds and is incorporated by reference in section 120 of schedule iv of the mvsr. on november 20 2013 the motor vehicle tire safety regulations were published which introduced new testing requirements within canada motor vehicle safety standard cmvss 139 new radial ply tires for motor vehicles with a gvwr of 4 536 kg or less g tbt n can 358 add.1 . the intent of cmvss 139 is to provide more stringent safety compliance standards for passenger car and light-truck tires. most passenger cars and light trucks sold in canada have a gross vehicle weight rating gvwr of less than 4 536 kg and can hence use cmvss 139 compliant tires. however vehicles having a gvwr over the 4 536 kg threshold would fall under the tire and rim selection rules found in tsd no. 120. due to their use profiles it may be desirable in some cases to use cmvss 139 tires on vehicles having a gvwr of over 4 536 kg. revision 1 of tsd no. 120 did not specifically allow for such applications. as a result tsd no. 120 is being updated to allow manufacturers the choice of installing the appropriate tires meeting cmvss 139. in all cases the gross axle weight rating requirements of tsd no. 120 s5.1.2 must be met. this revision would be consistent with the u.s. interpretation of the applicability of federal motor vehicle safety standard fmvss no. 139 tires to fmvss no. 120 vehicles.