I use a synthetic blend in my everyday drivers. I used to use full synthetic, but found it tended to leak as the miles racked up on the cars, and we can't have a dirty garage floor. I use 10w30 regular Valvoline in my GT350 and change the oil every 1000 - 1500 miles. Where I live, my car is "put up" for up to 6 months a year because of salt and snow. I have heard that the synthetic oils do not have the same properties to help prevent rust/corrosion as a car sits for a long time. Does anybody know if there is any truth to this? I would like to switch to synthetic. Jim
