[sfair74]

Hi,

I recently purchased a 2017 Toyota Yaris L hatchback. I have added factory cruise control but am otherwise stock. I have run some fuel system cleaner through the first tank of gas. It's still using the factory 5w-30 oil from the dealer and has yet to reach the next OCI. I plan to switch to Mobile 1 0w-20 EP when the time comes.

I drive around 25,000 miles per year. My drive is mostly 50 to 55 MPH with some 25 to 40 MPG stretches and may contain some 70 MPH expressway.

When I first got the car I was getting around 37 to 38 MPG on the lie-o-meter. As colder temps and winter blend gas has set in I'm getting 35 to 36. I typically get significantly above the listed highway mileage as my average but i'm quite disappointed in the MPG so far.

I think it would greatly benefit from a upper grill block and maybe a partial lower block. I don't have a scan gauge installed yet and will probably hold off till the dealer replaces a wiring harness next month on my car as part of a recall.

The thing I'm interested in is it worth it to swap wheels for lower weight and aerodynamics? I previously owned a 2001 Honda Insight and those wheels were light weight and have the same 4x100mm holes spacing and a very close offset to the Toyota Yaris. I have tracked down a set of salvage insight wheels and lug covers for under $200. Going to a 14" aluminum wheel with great aerodynamics should help compared to the stock 15" steel with hubcaps.

I am also a huge fan of Nokian's all weather tires. I have my sights set on their new WR-G4 tires. Unfortunately the only 14" size for that particular tire is 185/65-r14. The stock tire size is 175/65-r15. The purposed 14" tire has a higher weight rating so there shouldn't be any safety concerns. It's obviously 10mm wider than stock and about 2% smaller diameter. The total diameter of the tire is around 1/2" less so it should lower the ground clearance by 1/4".

Unfortunately the car is already geared pretty short with a traditional 4 speed slush box automatic. I fear the changing the tire size to be 2% smaller may negate the expected fuel savings from a lighter wheel and tire package and aerodynamics.

The other hangup is I would either need to buy a new set of TPMS sensors at $60 or pay probably $16 each to have them removed from the old wheels and have them moved to the new.

Is it worth the trouble and $250+ to swap to wider shorter tires in the name of aerodynamics and lower wheel weight? Another option is to get a set of clip on racing disks for around $100. I plan to drive the car for 3 to 8 years as of now.

Thanks for your suggestions.