In Reply to: Gas Mileage - Re: Oil Change posted by Lisa Ryckman on 08/01/01 at 6:21 AM:
If you change your oil from a petroleum based oil to a synthetic oil (poly alpha olefin type) you should realize a savings of 3 to 5% in fuel.
To max out the benefits of a synthetic oil, it is best to use synthetics throughout the drive train. Check with the vehicle manufacturer for use in the transmission. This is very important with Chryslers.
The reason you will see an increase in mileage is the fact that the molecules of a PAO synthetic are all about the same size. In a standard oil, ther are molecules of different sizes. This is because the oil is a fraction of crude oil.
Having molecules all the same size reduces friction. Less friction equates to more mileage.
To go even further in your quest for mileage, add
a high flow air filter like a K&N (or similar).
Also look in your owners manual for tire inflation pressures. They usually have a range. Higher tire pressure means better mileage. My car tires have a range of 28 to 34. I run at 32PSI.
Make sure you get a PAO synthetic. Some manufacturers say there product is a synthetic when it is only highly refined mineral oil.
Hope that helps