First off I'm new to the boards so i'll tell you all im switching over to amsoil 5w-30 and the SDF-42 filter on my 2002 Dodge ram 1500 with the 4.7 litre motor. it has 20k even as of today..=) My usual driving habits are a 3 mile each way trip to work so the motor rarely warms totally up and once or twice a month trip into town which is 75 miles each way. about once or twice a year I tow a 21 foot camper here in the high mountians of colorado. I usually change oil dino oil (5w-30 valvoline and mopar filter) ever 3500 miles. do you guys in the know see a good improvement wil a change to synth? This motor runs VERY well and burns 0 oil. I want this truck to last me at least 10 years. THANKS!