2010 Prius Only Getting 32 Mpg Due To Wheels/tires...need Recommendati

[GoldenKiwi]

I bought the car six weeks ago with 18" aftermarket wheels and Z-rated tires. I figured I might be taking a small, maybe 2-3 mpg hit with this set-up and it would be worth the sacrifice, but I am getting only 32 mpg. I need to find replacement wheels/tires, as this defeats the whole purpose of having a Prius.

I'm not a fan of the standard 15" wheels and would prefer not to go with those even though they would give me optimal mpg. Right now I'm most interested in the Persona 17" wheels, although I would take a 4-5 mpg hit using those. I have no idea about what tires I should get. I am looking for other wheel/tire suggestions that would minimize my mpg loss to no more than the Personas would.

Here are the wheels on the car now:

http://www.tirebuyer.com/wheels/konig/32mb-deception/p/wv227000829?cid=sce_google&CAWELAID=739323990&catargetid=1389777207&cadevice=c&cagpspn=pla&gclid=CJyH-a2vv7gCFQ9eQgodiBsArw[1]

Tires (only site I could find that had the exact match):

http://bbs.kakaku.com/bbs/K0000454415/[2]

Edit: I live in San Diego, winter tires are not necessary.

[Awebb180]

first step get some decent tyres on the car and get the alignment done. cheap tyres can mess up the MPG quite a bit

Alex

[kithmo]

Assuming because you live in San Diego, that's 32mpg US gallons, which equates to 40mpg UK. The US EPA for the Prius is 50mpg, so you are taking an 18mpg (US) hit somewhere.

I you have 225/40 R18 tyres, the overall diameter of your wheel/tyre combination is almost the same as the stock 17" Prius wheels and the tyres are only 10mm wider so it shouldn't make a huge difference to the mpg. The rolling resistance of the tyre only makes a small difference, unless they are particulary sticky tyres.

There are many factors that can cause the loss of mpg such as;

1. Low tyre pressures

2. driving too aggressively

3. alignment problems (as mentioned above).

4. short trips (less that 3 miles) where the engine hasn't fully warmed up

5. cold weather using the heater a lot

6. Hot weather using the AC on high a lot

7. carrying too much weight about such as tools etc.

to mention a few.

I would recommend over inflating the tyre pressures a little and having an alignment check as the first steps, as that is probably the cheapest option. If that doesn't work then consider if any of the above points apply before shelling out $ on new wheels and tyres.

[MLW2233]

My Gen 2 is now achieving 65 mpg in easy driving in hot weather. Just fitted Michelin Energy savers plus. Bit early to say, and the driving conditions are almost perfect, but I feel they are worth 3-4 miles mpg extra. 40 mpg is terrible.

Don't shun 15 inch wheels. This is not a Ferrari. Mine are 16x55x195 and I would love to have 15x 65x 195's if only for the subtle improvement in ride. They cost a lot less as well. It is a matter of personal choice but I regret the move to put all cars on massive steroid tyres with low aspect ratios that shake your fillings.

Glide and travel in comfort.....it is what a gentleman does!

[GoldenKiwi]

My Gen 2 is now achieving 65 mpg in easy driving in hot weather. Just fitted Michelin Energy savers plus. Bit early to say, and the driving conditions are almost perfect, but I feel they are worth 3-4 miles mpg extra. 40 mpg is terrible.

Don't shun 15 inch wheels. This is not a Ferrari. Mine are 16x55x195 and I would love to have 15x 65x 195's if only for the subtle improvement in ride. They cost a lot less as well. It is a matter of personal choice but I regret the move to put all cars on massive steroid tyres with low aspect ratios that shake your fillings.

Glide and travel in comfort.....it is what a gentleman does!

Which wheels are you using?

[johalareewi]

Don't shun 15 inch wheels. This is not a Ferrari.

+1.

I am really pleased with my stock 15s. Replacement tyres are abundant and affordable.

And underneath the plastic hubcaps, there are alloy rims.

Glide and travel in comfort.....it is what a gentleman does!

+1 again

[theoilburner]

We have the 17" wheels on our T-Spirit, and to be honest, I'd rather have the 15s from the lower model. The tyres are literally half the cost, there's no problems with high kerbs, and the fuel economy would be better.

This obsession with silly wheel sizes gets on my nerves, especially when it costs money on fuel on a car that's supposed to be all about efficiency! Rant over! :)

If it wasn't for insurance hassles, I'd swap the 17" silliness for a nice set of 15" steels any day.

[wass]

If you want big wheels and little tyres, then go for it Jeff. I regard our prius as utilitarian transport with absolutely no sporting pretences whatsoever and wouldn't bother with expensive wheels and grippy, fast wearing tyres. On the other hand, I wouldn't be running a jaguar convertible on high profile eco-tyres either!

[Opifex]

We have the 17" wheels on our T-Spirit, and to be honest, I'd rather have the 15s from the lower model. The tyres are literally half the cost, there's no problems with high kerbs, and the fuel economy would be better.

This obsession with silly wheel sizes gets on my nerves, especially when it costs money on fuel on a car that's supposed to be all about efficiency! Rant over! :)

If it wasn't for insurance hassles, I'd swap the 17" silliness for a nice set of 15" steels any day.

Completely agree.

I have read that the fashion for low profile tyres is the result of collaboration between car manufacturers and tyre makers. The car manufacturer reduces their costs by getting heavily discounted tyres, and the tyre manufacturer gets a captive market for expensive replacements in the future.

[theoilburner]

Wouldn't surprise me at all. Prius tyres on BlackCircles.com with Conti EcoContact Tyres (so I can do a reasonable comparison): 15" is £67.90, 17" is £121.39.

According to my maths the 17" tyre has 9.14% extra surface area (plus extra in grippy area). The surface area of the grippy part is about 11.5% bigger, so that adds up, and I suppose the side-wall of the tyre might have extra reinforcement...but for how much extra? I can't believe it really costs them nearly twice as much to make it...

[Parts-King]

As my old mentor used to tell me.................It's only the profit that makes it dear! (expensive)

Kingo

[MLW2233]

I am on 16 inch wheels but would love to be on 15s, if only for the improved ride.

[barrycoll]

I am on 17"'s but would love to be on 15s if only for the improved ride....

but maybe a run in a 15" shod Gen 3 would be a good idea first, as the improvement may/ could only be marginal, and not worth the effort.....

I have a feeling that the only area that Mr Toy has skimped is on the un-sophisticated suspension (plus the plastic interior of course)

[kithmo]

I am on 17"'s but would love to be on 15s if only for the improved ride....

but maybe a run in a 15" shod Gen 3 would be a good idea first, as the improvement may/ could only be marginal, and not worth the effort.....

I have a feeling that the only area that Mr Toy has skimped is on the un-sophisticated suspension (plus the plastic interior of course)

So true, I test drove a Plug-in which has the 15" wheels and it was just as noisy and only marginally softer than the 17" I had on the Gen 3. The Prius+ I have now is shod with 17", albeit slightly higher profile at 215/50, and it is much more refined than the Gen 3.

[johalareewi]

I have a feeling that the only area that Mr Toy has skimped is on the un-sophisticated suspension (plus the plastic interior of course)

Mr T didn't skimp on the plastic interior. That massive plastic dash is very expensive eco plastic!