Synthetic motor oil

I did my first oil change on my recently acquired 2004 Chevy Venture. My mileage on a 700 mile road trip came in at 26.9 miles per US gallon (8.74 liters per 100 km). (This was 90% moderate highway driving.) I can't find my "before the oil change" mileage, but I think it was 5 - 10% less. With the amount of driving I do, I should save $300.00 to $400.00 in a year. Are those of you that use synthetic oil seeing similar results?

I shifted over to full synthetics about 30 years ago. It the time i was running a new f-100 with a 302. Average highway mileage went from 11.5 to 14 mpg with a noticeable improvement in power. There are a lot of advantages to the synthetics.

With a standard motor oil you really should do a oil change every 2000 - 3000 miles. You can safely go 15,000 miles between oil changes with a high quality synthetic. That's an 80 % reduction in the waste oil you're producing so that's good for the environment.

The synthetics give you smoother cold weather starts. ( That's where most of your engine wear comes from. )

They have a much higher vaporization point so you aren't pumping a bunch of emissions up through your PCV valve. That's better for air quality.

I've never had a motor fail in all this time. I even knew of a gent that was running a VW microbus with a cracked block. The base oil must have been 50% synthetic & 50% gasoline but that engine still wouldn't quit.

LOL ..... i guess you can tell i'm in favor of the synthetics ?

I run Mobile 1 15,000 mile blend I see a bit better mpg but I change my oil every 15-30k miles huge amount saved in oil changes .
and at 32,000+ miles I could not tell the difference between "old' oil I was changing or new .