Thinking of getting 17s but i dont want to lose mpg's

The simple answer is stick with the 15s....

16s are a good compromise and will reduce the hit and may provide more LRR tire options but expect at least a small loss.

It's a sad fact but upgrading to 17s will cause a drop in mpg. I have yet to figure out a way to minimize the loss. I have lightweight wheels and new LRR model tires yet I still drop quite a bit compared to my LRR 15s. I've yet to see anyone with factory 17s swap to 15s to check the loss yet you'll always get one or two claiming they suffer no loss.

 

Yep. Or, look at the loss another way: Car and Driver: Mileage? No, it's Your Gallonage that Really Counts | PriusChat. Run some "gallonage" calculations yourself (e.g. 50 to 45 mpg vs. 20 to 19, 20 to 18, etc.)

 

Thanks. I always forget to add that part and it becomes quite important when making a choice like this.

In my case the 17s cost quite a bit to run because I average over 26,000miles a year now. If I was under the national average of 15,000? I wouldn't sweat it but at this point I could save enough for a brand new set of tires if I ran the 15s instead.

 

The main reason 17 inches get less MPG is weight, Light 17s would get better mileage (and cost more)

Weight distribution plays a role as well, more weight at the rim is worse than more weight at the hub, but you have little control over that.

You could drop $2500 here Kodiak Racing Wheels - Custom lightweight race wheels for performance and racing

 

Jim, unfortunately the tires area also quite a bit heavier. My wheels are approx. 15-16lbs but the tires are 5lbs heavier than OEM so the brings my total to about 6-7lbs heavier than OEM 15s with Integrity tires yet my mpg still takes a huge dive. I totally agree that weight hurts mpg but I think that tire width, construction, and compound play a larger role or else the car is super sensitive to wheel weight. I only say this as a warning to anyone considering spending big bucks for lightweight wheels.

 

Can't agree. 3 Gen 17 inches rims come fitted with 215 tyres, and that width holds more rolling resistance itself, and more aerodynamic drag.
Weight does not come in first approach for highway fuel consumption, as we've seen in recent EPA testing for Prius C and 3Gen estimates...The latter weighs more and consumes less.

 

I also forgot to mention that a nearly similar loss in mpg comes about when someone switches from a LRR 15" tire to a non-LRR 15" tire. This is another reason I blame the tires more than the weight of the wheel despite my rants about wheel weight and rotational mass.

 

How about a set of these, if pics don't come out, I'll look for a link.

They have been testing these for several years now. Resilient Tech was developing them for the military application.











Amazing new tires.........................



Michelin Tires... Absolutely SCARY looking... Look for 'em in August. These tires are made in South Carolina , USA .



SEE THROUGH TIRES

Radical new tire design by Michelin. The next generation of tires. They had a pair at the Philadelphia car show.



Yes, those are 'spoke' like connections to the inner part of the tire from the outside tread 'wrap!' The next picture shows how odd it looks in motion...



Makes you wonder how the ride feels doesn't it?









These tires are airless and are scheduled to be out on the market very soon. The bad news for law enforcement is that spike strips will not work on these. Just think of the impact on existing technology:

A. no more air valves...

B. no more air compressors at gas stations...

C. no more repair kits...

D. no more flats...

These are actual pictures taken at the South Carolina plant of Michelin.

Here's one link: http://hight3ch.com/airless-tire-from-michelin/

 

Wrong information. Rolling resistance, not weight, is a major killer of mpg.

 

If you don't already practice pulse and gliding, you can overcome the mpg hit by changing your driving habit (to hypermile 100% of the time). This would depend primarily on your motivation and won't work if you want to drive it like a regular car or are already doing the hypermiling techniques.

 

This, of course, is a generalization based on "normal" driving. The actual parasitic contribution of the various factors depends on the characteristics of the tire, the road surface, and environmental factors. For example, with a very hard tire running on a very hard surface (think train wheels on steel rails) over a level smooth surface, weight makes very little difference.

If the road surface goes uphill, then weight obviously becomes a factor. If the road surface is uneven, unsprung weight becomes a factor. If the road surface is soft, weight becomes a factor.

Likewise weight distribution is not a factor at steady speeds. When speed varies, however, weight distribution changes the rotational inertia of the wheel/tire assembly. More inertia means more power to accelerate, and more power to dissipate in a stop.

All of the factors contribute along with rolling resistance and aerodynamic drag.

Tom

 

Does this mean that the level five Prius gets worse gas mileage because of the 17 inch tires?

 

Yes but because EPA doesn't require every trim model be tested (or have a test submitted) for mpg, Toyota doesn't list the difference even though sheer physics and anecdotal evidence tells otherwise.

 

I wonder if the OP has considered going with aftermarket 15" wheels, assuming that he wants "the look" of a cool wheel and not necessarily the improved handling characteristics that a wider tire would yield.

 

Yes--but it's a rounding error. The UK specs differentiate between the 15" & 17" wheel cars, and (from memory) the difference is 2 - 3 %.

 

I don't understand. 2-3% would be 1 to 1.5 mpg, no?? Rounding error would be less than that.

 

Or simply removing the plastic covers to reveal the stock 15" alloy wheels?? Personal taste, some like them, some think they're ugly. Personally I don't think the stock 15" alloys are beautiful but (to me!) they look better than the plastic covers.

 

I've never understood the rounding error argument espoused by stream.

 

Given all the variables that affect MPG, 2 - 3% is a rounding error from my perspective.