Performance rims bad for fuel Economy?

gasoline
wheels

#1

2006 VW Passat Wagon V6, with factory “upgraded” VW 17" wheel set gets 14.6 mpg average on my 3 mile commute. It is stop and go for the 3 miles. I am very careful about acceleration. Added wheel weight, “rotational inertia” and wider tires must be part of the issue, but how much better milage improvement would I get if I trade in the performance wheels for standard wheels? Would this downgrade be worth it to save money?

Performance wheels are so common, especially on expensive German cars, is everyone just a fool?


#2

Wheels are not going to make any noticeable difference in fuel economy.
The V6 Passat is rated at about 16 MPG and your current 14.6 is going to fall into the perfectly normal category; especially considering you have a 3 mile stop and go commute.

Clean air filter, fresh spark plugs, proper tire pressure is about all you can do.


#3

“Performance” rims are usually 90% looks 10% performance. The really good ones are lighter and stronger than good old cheap steel rims, but cost far far more. Most such rims around today are far more expensive than steel but heavier and less strong. The only thing they are good at is making money for the dealer and looks.

That said the difference on mileage is so small as to be difficult to measure. Driving a 3 mile stop and go commute is usually a low mileage trip. If you tend to drive a little aggressive and find yourself using the brakes often, then that mileage is not so bad. If you want better mileage the best tool is a light foot. Easy on the accelerator and reading traffic so you need to use the brakes less is the best tool in the box for better mileage.


#4

I agree with the others that you will not see a noticeable difference in mpg by switching wheels. Keep what you now have.


#5

You can’t get good fuel economy with that kind of a trip.


#6

Whether an alloy rim is heavier or lighter than a comparable size steel rim is entirely dependent on the rim design and alloy. And a 215x40/18 on an alloy rim “upgrade” could easily be lighter than a 215x45/17 on a steel rim “standard size”.

But I agree with everyone that no difference in gas mileage would ensue by changi9ng to a steel rim.


#7

Nobody here knows the answer to your question because the information that you want is not commonly available to consumers. For example, the new Chevrolet Cobalt XFE has a 25/36 mpg rating. The highway rating is up from 33 mpg with a revised computer, a taller final gear ratio and low rolling resistance tires. An auto mfr has the buying influence and testing facility to find the lowest rolling resistance tires.

Rotational inertia due to wheel and tire weight will be a much less significant factor affecting gas mileage than tire rolling resistance at a steady speed.

Michelin sells a line of tires with low rolling resistance to help gas mileage. Possibly they have your size.


#8

The guys have pretty much summed it up…theoretically lighter rims should bring better fuel economy, BUT the actual difference will be a very small percentage of the over all fuel spent. I note most long haul trucks have alloy rims. Less rolling weight. The percentage of fuel being consumed by the mass of the rims themselves is probably only noticed on a yearly or longer basis. For your 3 mile commute you aren’t even getting the engine warmed up. The fuel losses in a cold engine are going to run far away from anything you might save in the best case scenario in the rim division. Save the rim money for gas and lighten up on the lead foot.


#9

p.s. Don’t change anything until you have worn out your existing tires. The cost of the new rims will far out weigh any small savings you realise in fuel. The wider tires will contribute some rolling resistance, but you still probably won’t save enough to pay for the rims (unless you get them for free). At least this way the cost associated with the rim change will be the same as buying the new tires. The new tires might be cheaper than the performance tires you have now will be to replace, and then there will be an acrual savings.


#10

Thank you all for weighing in on this!
Sounds like there is clear consensus that the rims don’t matter that much, BUT perhaps this little video might make you think twice.
I hope that you can view the attached video that I took at the San Francisco Exploritorium. (I attached a photo of the event that illustrates the point just in case. The video is of a rolling table with a constant slope and wheels with the exact same weight, but placed closer or further from the axle (study of weight distribution).
Hard to believe but, the 2 rolling wheels at the left were started at the same time (ignore the guy in the video who places a third wheel at the right while I was filming with the last of my camera’s memory).
I think that the video is interesting because it shows that the wheel with the weight further from the axle (like a performance rim) roles much SLOWER than when the weight is closer (like a standard rim). I would have thought it the other way around!
Seems like the performance wheel requires much more power to get it started from a stop and since start acceleration is so important to fuel consumptions, seems important.


#11

Excellent link. However the extreme difference found in this great illustrative experiment (and I mean that as a compliment) won’t be found in the difference between an alloy rim with tire and a steel rim with tire. The variant will be small. The difference to the automobile (assuming the rolling circumference stays the same) will be miniscule.


#12

ok4450 is correct, as usual. It’s not the rims, it’s the 3-mile commute. No matter what you do, if you only drive 3 miles each way, you’ll never get great fuel mileage. The engine and drivetrain never achieve normal operating temperature on such a short drive.

Changing wheels/tires would cost a fortune and yield no significant gain in fuel mileage.

Why do you need a V6 to drive 3 miles?