The more time that I spend on this forum the more I question my oil requirements. my OCI is every 3 months and my cars rarely see more than 3000 miles in 3 months. My wife and I both live and work in a small town our cars rarely get up to full temp. I do tow a 24' camper in summer and a snowmobile trailer in winter. My wife is a EMT IV Tech so that means when she gets a call she starts the car and emedeley beats the [censored] out of it. so now that you know what my cars go through my question is should I run synthetic or dino. I am currently using M1 in the GP and RP in the Silverado. The Jeep is a work beater that gets Resoilute oil If i should stay with synthetic should i try something cheaper like citgo. I will not go longer than 3 months OCI due to the low short trips and excessive idling. Suggestions please. One more thing I do not shop at chinamart so no ST Suggestions