Hello Guys,

I have 00' TL. I recently (about 2 months ago) changed the tires from stock 205/60/16 to 215/55/16 Yoko V4s after reading the reviews on here and yes definetly they are great tires. The drive is great and real quiet as compared to the Michelins, BUT I noticed a drop in my mileage. I used to get like about 315 miles/tank now I get like 280-290. I thought since my ride has about 75K on it the next scheduled service would fix it. So this time I got the dealer to put synthetic oil instead of regular. I honestly dont feel much of a difference and my mileage is still not back up. Also is it true that once you go synthetic you cant go back to regular oil?

Any advice would be really appreciated.

Thanks all...

 

You're not going to 'feel' any difference with a synthetic.

Not true.

Forget about miles/tank, it's meaningless, what mpg are you getting?

 

Well, the sidewall on your old tires was (205*.60) = 123mm. The new tires are (215*.55) = 118mm. You have decreased the diameter of your tires; I am not surprised your mileage decreased.

 

There's a 1.5% difference (80.7" vs 79.5") in the circumference between the stock tire and the new one. He's claiming an 8% reduction (315 vs 290) in miles/tank.

 

Hmm.... thats interesting. I never thought of it like that ... wow.. I guess maybe its right ... ?????

 

Well I normally measured my mpg by how many miles I got per tank.. so with 315 I always thought of my mileage to be around 22.34 and now its like around 20.56 of course me counting the tank capacity to 14.1 gallons

 

If your assumption (14.1) of how many gallons you put in the tank is off by half a gallon, your mpg could range from 21.6 to 23.2. That's why using how many gallons you actually put in the tank is the best way to track mpg.

I don't see how the new tires could cause an 8% reduction in mpg.

 

The stock Michelin tires as much as they suck, have very low rolling resistance, meaning good gas mileage. You've traded to a new tire that is quieter and probably grips better but the tradeoff will be decreased gas mileage.

 

I agree, but an 8% reduction?

 

Wow .. interesting. I guess in the end a little sacrifice on the mileage is worth the nice ride.

Wondering.. if there are any mods I can do to up mileage and power ...

 

I guess then I might as well switch back to regular oil since that aint helping much.... .... save some moolahs there

 

using syn doenst cost more. you can go over twice teh mileage (actually 3-4 times, im running 15k intervals on mine) so syn is alot cheaper.

as for the mileage, it could also be due to winter formulas in gas right now, that and whats your air pressure? try bumping it up some if your at the crappy 32 psi recomended rating jump up to 35-37 and give that a shot

 

Yeah, 35 psi is what i run and the tirewear is even