If one is motivated to use a diesel fuel additive, the Schaeffer stuff I use has been a real good value and does a great job on all my diesels. Since I started using it a little over 2 years ago, I have not had any fuel filter issues in winter as before, even at -25F using basic diesel gotten at normal truck stops, which is not always spiked with #1 diesel as it should be in cold weather. The stuff is very cost effective, runs me about 1-2 cents per gallon of diesel fuel. I use their winter 137 ULSW and their summer 137 ND. Some of us that have Webasto in cab diesel fuel fired heaters for times that the semi trucks are shut down in cold weather, usually have some maintenance issues with them regarding diesel fuel. I am on the 4th winter with my current Webasto and it has not had any issues since using the Schaeffer products.