Declining gasoline/distillate demand ratios in the Canadian petroleum product market have further aggravated the traditional shortfall of low cloud point middle distillate fuels in the winter and created a need to improve refinery flexibility. The advances in performance of wax crystal modifier additives have been used to formulate No. 2 Diesel fuels with good response in the Low Temperature Flow Test (LTFT). Field testing of selected flow improved diesel fuels both in controlled fleet testing and in a portion of the Canadian market, has demonstrated that such fuels provide satisfactory vehicle operability well below the cloud point or wax appearance point temperature. In the vehicles tested in controlled fleet tests, the LTFT pass temperature correlated well with minimum temperature for vehicle operability.