I've seen people mention casually that they think switching to 205/50/16 tires on Sport wheels resulted in 1 or 2 mpg drop in fuel economy. I'm wondering if anybody out there who tracks each fill up and keeps a log of actual mpg over multiple fill ups (not what the display says) can provide any concrete numbers for original tires versus after a changeover to the wider tires.

I know, do a search, but I'm not finding any actual data out there.

Thanks!

 

yes, i suppose i did get a bit of a MPG drop. 1-3 MPG is negligible to me, though. i'd rather have stickier, wider and overall a safer tire with my 205/50s. i've been keeping track of my MPG since day one.

1-3 MPG loss is what i'm experiencing. i have heavier wheels (16*7.5) and the 205/50s are heavier. not much of a sacrifice for me.

 

You can sift through my Fuelly site (link in my signature) to see for yourself if you can find any trends. As they say, your mileage will vary, and it's hard to compare each tank due to different driving conditions and weather conditions.

I feel that overall I have seen a slight drop. I got my tires in June, and then promptly took a hectic trip from Michigan to Colorado and back. Both ways I drove into a nasty headwind and had a heavy load in my car, so the mileage sucked, so you kind of have to disregard those tanks. Since then, I've had a few tanks in July through September that were mostly just my normal commute, and comparing them to the same types of tanks in April and May, it seems that I used to get closer to 38 more often, and now am closer to 36-37. Hard to say for sure though.

 

typically wider tires will have more drag but it depends on the rolling resistance of the tire itself. the tread pattern, compound, psi, all varies the mpg too so it's hard to really generalize.

 

I'm interested to see if anyone is using FuelMax tires and their corresponding mileage after the switch...although most of the people here want sport tires, I can't imagine that there aren't people who would have these to improve (or attempt to) mileage. I doubt I'll be the first to switch to GY FM 205/50's/16's...

 

the thing about very low rolling resistance tires is their compound is hard and dont work very well as all season tires in colder weather. so one ends up buying that and winter set....not much savings there if you need 2 sets.

if you have snow then i suppose you'd want a snow tire set anyways so i can understand in that situation... im not sure if i could tell a difference in mpg from the tires.. snow tires vs all season tires. in the winter our state uses oxygenated gas so it burns faster... with more use with defroster obviously it hits mpg... so at the end not sure if tire rolling resistance is even significant to the total saving you get at the end.

 

Too many variables, but generally speaking, if you're talking about putting on heavier tires with less aero, you will lose efficiency. How much depends on your situation.

Can you explain exactly how 205/50's are safer? Braking distance and grip will be negligiable when you're talking about everyday driving conditions between the two tires (and I'm talking the SAME tires, different sizes). "Stickiness" depends on the compound, not tire size. I think it's a common misconception that wider = safer. It really depends on your situation. i.e. I'd rather have skinnies when driving in rain or snow.

 

mostly, i was just speaking of how much safer my current tires (yokohama avid envigor all-seasons) are compared to the stock dunlops which i consider death traps. i didn't mean to imply that a wider tire was safer given the same brand and model of tire.

 

You are correct. But I would contend that they do relatively well (with the exception of ice/moderate to deep snow) in the winter. They did okay on our CR-V (and we live 25 miles from civilization!). Nothing to write home about, though.

 

Ah, ok. Yeah, I've never had any luck with Dunflops.

 

There's really no loss in cost of you have two sets because your original set will last you longer. (time-wise) This is also given that you don't switch over to new tires on your stock rims but have another set of wheels. With snows, you also end up with a safer, more capable, ride.

I track my economy and I'll be switching to 195's or 205's when next spring comes around as my bridgestones are worn down and my snows will go on in another month. That said, my commute has drastically changed as I no longer work 26 miles away from home, now 6 miles... so my stats are going to change, likely my economy will drop as a whole.

~SB

 

Choice of tires goes a whole lot further than skinnies... for rain with wider tires is a NON issue, as long as they're built for it. Plenty of ultra performance wide tires that can easily handle tons of wet. Skinnies in rain isn't going to be better... you're starting with less contact patch and it will be even easier to hydroplane. Just need really good wet channels for awesome wet performance.

Snow is a whole other story though, but winter tires in wider sizes can easily outperform all-season skinnies.

Low rolling resistance tires are the ABSOLUTE JUNK... tires are paramount to vehicle safety if you ask me, and low rolling resistance tires are just plain asking for trouble. Speed, bad weather, crosswinds, etc will cause plenty of issues. And the Bridgestone/Dunlop tires on the Fit, are pretty close to the bottom of the pile.

Seriously - what's a 1-3 mpg drop in mileage, for tires that stick to the road? There are plenty of Fit owners that still get great gas mileage, without resorting to the stupid side of stuff like skimping on tire traction, or over-inflating them.

 

In round numbers, you'll use about 10 gallons more gas per year for every drop of 1 MPG in fuel economy (based on 10,000 miles per year and a baseline of 33 MPG). So a 1 MPG loss is pretty minor. 3 MPG starts to add up though - about enough to pay for the tires.

 

i also have seen a 1-3 mpg drop.
i did my tires over a month ago. so check
out my fuelly below for more details.

 

30 gallons even if gas was $4/gallon... $120/year extra.

Safety and peace of mine with better tires causing loss of 3 mpg... priceless!

I notice the 3 mpg seems to be coming from those getting already the higher end of MPG, ie. high 30s. Somewhere about an 8% drop in fuel economy, I guess 3 MPG is noticeable to some extent.

Just for comparison, a good sushi meal at a restaurant each week... $50 x 52 = $2,600. Good for like 650 gallons of gas at $4/gal... or 19,500 miles at 30 mpg!

I stopped worrying about gas cost as much, once I figured out that gas isn't all that expensive, compared to eating out, etc. What's the average person pay for triple play, or smartphone service per month, etc?

The $120/year difference now looks like a drop in the ocean.

 

Niko - thanks for posting the Fuelly. It's hard to tell without averaging data over a lot of fill ups, but it does look like you've dropped off a bit. 39.9 overall average MPG is pretty impressive with an AT, even with your high highway %. Do you take it easy speedwise?

huisj - thanks also for the Fuelly data. Like you said, it's pretty much a guessing game trying to pull out a trend.

Neteng - a few drops are OK, but if you're not careful they can turn into a flood.

 

That's normal.....If you want the look, you have to trade off with poor MPG

 

Yep, good rain tires will provide a solid footing. But I will say that given the SAME tire, I'll take the skinnies driving through rain. Driving through puddles at speed with 185's and 215's, I'll take the 185's. Simple physics. Now, wet performance, that is another story. I should have clarified that. My bad.

Regarding winter tires, yes, snow tires are obviously better. Give me skinny snow tires and I'll have no problems with performance in snow and slush.

 

Even if you replaced tires with the exact brand and size that came stock you would see a slight reduction in mpg for new tires. Worn out tires have less rolling resistance and are smaller in diameter. So of course switching to 205/50's you will also see a slight decrease. I've figured about 1-2 mpg drop since I mounted my 205/50's, half of that being for new tires and half for slightly wider and a couple pounds heavier.

But my V rated Hankook's cost only $70 each and cheapest 185/55 size tires were about $125 each. So I saved $220 switching sizes and that buys me enough gas to make up for a 2 mpg loss over 45K mile life of tire. So cost of use is the same but with definitely increased handling, traction and braking. Of course that will depend on the actual tire you choose though.

_

 

i used to keep it under 63 but now i go no more than 70.