Sythetic oil got me 40mpg

[ardvark2175]

Bought a 2012 Yaris LE automatic. I was pretty much getting the advertised fuel economy of 32 / 35. The following service was done to the vehicle. 50 miles at purchase, installed K&N washable air filter. 500 miles, oil change standard Valvoline 5w30. 2500 miles, oil change with standard Valvoline 5w30. 5000 miles, oil change with Semi synthetic Valvoline 5W30, cleaned air filter. 10000 miles oil chance with full synthetic Valvoline 5W30, transmission flush with AMSOIL Signature Series Fuel-Efficient Synthetic Automatic Transmission Fluid. Immediately after going full synthetic I gained 5 mpg. I get 40 mpg regularly now driving the same 180 mile route driving 60 and 65. Just thought I would share. was pretty jealous of the 40 mpg guys, but am happy to be joining the club.

[IllusionX]

cooler temperature affect fuel economy. keep that in mind.

[ardvark2175]

Thanks IllusionX. I figured lower temps probably meant people weren't running the ac. Have since learned I should get better mpg in cooler temps ac aside. Looking forward to checking is out when a make a drive winter. The bet mpg I have gotten so far was 46mpg. I set the cruise at 50mph and stayed there. I'm looking forward to doing this again on a cool morning or at night now that I have full synthetic. Ill post how I do on my 180 mile trip next month when I come back from work.

[Kar98]

My wife and I took last week off, and anywhere we went, we took the Yaris. Suddenly, gas mileage was 40 mpg for fun drives in the countryside, as opposed to the usual 33 for driving in gridlocked city traffic.

[caper26]

lower temps REDUCE mpg. Trust me. Click on my "fuelly" log and check jan/feb, lol. Ugh.
That aside, I have just changed to Castrol Edge Full Synthetic with Titanium Fluid Strength Technology 0W-20 (http://www.canadiantire.ca/AST/browse/4/Auto/Winter-Driving/SyntheticOil/PRD~0289256P/Castrol+EDGE+with+TITANIUM+Fluid+Strength+Technolo gy%2C+4.4L.jsp?locale=en). The dealership had "upgraded" my oil (at my request) during the very first oil change, and that is the weight they have been using, so that is what I bought to do my own. I only had to pay the difference because I had free oil changes with the extra warranty. Is "titanium fluid strength" snake oil? Who knows, but it was on sale and the cheapest one there, lol. Will need to finish the gas in this tank before I can get an accurate mpg, but temps are falling everyday, so it isn't the ideal conditions to do a comparison...

[roxy1]

in my experience, winter gas formulation hurts mpg considerably more than colder air. I will see a 10% hit at any given temperature with winter vs summer gas. many parts of the country start with winter gas around early October.

still, even with winter gas I am getting 43.4 mpg (actual calculation) per tank on a mostly light suburban and 15% city commute.