So, I've got the ls and it gets on average 31mpg, mostly because we don't see speeds above 55 in oregon and 45 most of the time.

However, would switching to a synthetic help me get better mileage. I know they have probably already been disscussed before, but I also need practice posting things in the right location

 

there may be slight increase. I was just looking this up mobil 1 has some of this info on their website...

EDIT: here is the link

http://www.mobiloil.com/USA-English/...AQs.aspx#FAQs1

they are saying you can up to two percent increase, which would be about 9 to miles per tank but you have to use thier new advanced fuel econmy synthetic oil. Its 0w-30 or 0w-20 oil. They also said that it would be roughly about 400 in life time savings based on 22.5mpg and 12,000 anuall miles... so we may see more since our cars are better on gas then what they tested with. Right now its not enough to sway me to switching to their advanced fuel economy synthetic, from the regular 5w-30 synthetic. Also GM recomends 5w-30 for our cars, not 0w-30 or 0w-20

 

just put in mobile 1 full synthetic today, i could prob let u kno in a couple days if i notice a difference

 

Yeah, I'm not seeing a benifit in 34 bucks a year, wonder if there are other options.