Stricter EPA testing for 2017 model year - be careful making comparisons - Fuel Economy, Hypermiling, EcoModding News and Forum

MetroMPG · 06-16-2016, 04:13 PM

The EPA has introduced stricter fuel economy testing methods, starting with the 2017 model year.

The changes apply to coastdown testing to determine a vehicle's aerodynamic and mechanical resistance -- values which are then fed into the chassis dynamometers used during the actual laboratory fuel economy & emissions tests.

Remember how a few automakers got in trouble in the past few years for using "erroneous" (haha) road load values which under-reported aero/mechanical drag and therefore inflated their fuel economy ratings vs. real world results? Hyundai, for example. The same thing has been going on recently in Japan with Suzuki and Mitsubishi both getting in crap for gaming road load values for their government's tests.

The takeaway:

Keep these changes in mind when comparing the EPA ratings of 2017 vehicles to previous years. They're not 100% apples-to-apples.

Even a vehicle that carries over basically unchanged between 2016 and 2017 will likely have a lower MPG rating, as these examples show:

Acura ILX (2.4 L, Auto) HWY MPG: 36 (2016) vs. 35 (2017); Combined: unchanged
Buick Regal (2.4 L, Auto) HWY MPG: 31 (2016) vs. 30 (2017); Combined: unchanged
Ford Fusion hybrid (2.0 L, Auto) City MPG: 44 (2016) vs. 43 (2017); Combined: unchanged (Ford's press site says the 2017 uses more efficient motors and programming, yet its rating still dropped)
Kia Rio Eco (1.6 L, Auto) HWY MPG: 37 (2016) vs. 36 (2017); Combined: unchanged
Mazda CX-3 2WD (2.0 L, Auto) HWY MPG: 35 (2016) vs. 34 (2017); Combined: unchanged
Toyota Camry (3.5 L, Auto) HWY MPG: 31 (2016) vs. 30 (2017); Combined: 25 (2016) vs. 24 (2017)

Not surprisingly, most of the changes affect the highway rating (except for, interestingly, the Ford Fusion hybrid). However, the differences -- 1 MPG US in each case -- are small enough they may not change the vehicle's overall or "combined" rating (except for the Camry, which drops by 1 MPG).

But in the cut-throat world of marketing, where 1 MPG may make the difference between being able to trumpet "best in class" or not, keep your skeptical eyes open.

More info:

PDF: Determination and Use of Vehicle Road-Load Force and Dynamometer Settings (U.S. EPA, CD-15-04, February 23, 2015)

Quote:

The purpose of this letter is to refine and clarify the procedures to be used by vehicle manufacturers in establishing vehicle road-load force and dynamometer settings.

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EPA updates MPG sticker rules for 2017 model year vehicles

Hersbird · 06-18-2016, 12:03 AM

I wonder if the Elio will still get 84 highway? Do they have the testing standards out for 2023 yet?

Baltothewolf · 06-18-2016, 06:43 AM

Quote:

Originally Posted by Hersbird

I wonder if the Elio will still get 84 highway? Do they have the testing standards out for 3023 yet?

Fixed .

MetroMPG · 06-20-2016, 12:08 PM

Green Car Reports has picked up this story:

Gas mileage ratings for some 2017 cars to fall as EPA tweaks tests

MetroMPG · 06-20-2016, 04:42 PM

Yes, wouldn't it be interesting to know just how many they've audited and discovered "discrepancies"?

Of the relatively small number of 2017 models available on fueleconomy.gov to compare with equivalent 2016's, almost all seem to have dropped.

Hersbird · 06-20-2016, 08:29 PM

The first time I noticed this was when looking at the Ford Flex and Lincoln MKT "twins". Both had the same aerodynamic factor and therefore the same EPA ratings. I just had a hard time believing these have identical drag.

niky · 06-21-2016, 02:23 AM

It's amusing that with the leeway they get via legal loopholes, some manufacturers still went the extra mile in gaming the tests illegally.

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Despite the fact that they keep finding and closing these loopholes, I still hold that the EPA tests are as close as we can get to a realistic economy test among the major markets... and this development simply makes it even better.

Fat Charlie · 06-22-2016, 10:38 AM

Quote:

Originally Posted by Hersbird

I wonder if the Elio will still get 84 highway? Do they have the testing standards out for 2023 yet?

Doesn't matter. Who cares what a prototype gets?

Hersbird · 06-22-2016, 03:48 PM

Quote:

Originally Posted by Fat Charlie

Doesn't matter. Who cares what a prototype gets?

They are marketing it as so, I personally feel there should be some truth and accountability in advertising. They then also suck up all the money in the room that might end up going to something more realistic like the Arcimoto. Other potential 3 wheel companies see their claims and price and don't even try to get off the ground as they are impossible. So I made a joke out of them which I admit has become low hanging fruit.

Fat Charlie · 06-23-2016, 09:46 AM

No, you're right. I was looking at the lack of hope of their seeing production, you're looking at the problems it's causing that market.