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Ford relabels 2013 C-MAX Hybrid to 43 mpg, upgrades 2014 C-MAX Hybrid to boost fuel economy; pitfalls of the EPA “general label” rule

After re-labeling the 2013 C-MAX Hybrid with lower fuel economy, Ford is upgrading the 2014 C-MAX to increase fuel economy. 2014 mpg is not yet announced. Click to enlarge.

Ford has opted voluntarily to relabel the 2013 C-MAX Hybrid with revised fuel economy labels following EPA testing of the 2013 C-Max Hybrid. EPA had received consumer complaints that the vehicle did not achieve its label values of 47 mpgUS for city, highway, and combined driving (5.0 l/100km).

The new fuel economy estimates, as determined by the EPA, for the 2013 C-MAX Hybrid are 45 mpg city, 40 mpg highway and 43 mpg combined (5.23, 5.88 and 5.47 l/100km, respectively).

Original 2013 C-MAX
mpg label
New 2013 C-MAX
mpg label
Change in mpg (%)
City Hwy. Comb. City Hwy. Comb. City Hwy. Comb.
47 47 47 45 40 43 -2 (-4.3%) -7 (-14.9%) -4 (-8.5%)

Ford is also offering current customers of the 2013 C-MAX Hybrid a one-time payment of $550 (purchase) or $325 (lease) to offset the fueling difference. At the same time, said Raj Nair, group vice president, global product development, during a webcast this afternoon, Ford is upgrading the 2014 C-MAX Hybrid with new transmission gearing and enhanced aerodynamics to further improve its fuel efficiency performance.

The upgrades build on powertrain software updates Ford announced last month for the 2013 C-MAX Hybrid. Changes include:

  • Gearing changes that result in a more efficient transmission drive ratio;

  • New hood seal, front and rear tire deflectors, A-pillar moldings and the addition of rear lift gate deflectors to improve vehicle aerodynamics; and

  • New engine oil with reduced friction.

Ford expects the enhancements to the 2014 C-MAX Hybrid will improve customers’ on-road fuel economy, especially at highway speeds. Fuel economy label testing has not yet been done on the 2014 model.

2013 C-MAX and the General Label rule. In December 2012, road testing by Consumer Reports found the fuel economy on the 2013 Fusion Hybrid sedan and new C-Max Hybrid falling far short below the touted Ford (and EPA) triple 47 mpg (5.0 l/100 km) figures—i.e., 47 mpg for city, highway and combined—for both vehicles. (Earlier post.) Consumer Reports reported at that time that the two vehicles had the largest discrepancy between overall-mpg results and the estimates published by the EPA that it had seen among any current models.

Later that month, Ford responded that it standing by the ratings as determined by the current testing protocols. At that time, Nair said that “we absolutely agree with EPA that hybrids are far more variable in the test cycle compared to real world driving conditions in conventional vehicles. We are working closely with the agency to determine if any changes are needed for the industry relative to hybrid vehicle testing.” (Earlier post.)

After receiving consumer complaints, EPA acquired a 2013 Ford C-MAX hybrid, accumulated 4,000 miles to break it in, and performed fuel economy tests. Based on the results of these tests, EPA determined that the fuel economy performance of the 2013 C-MAX was significantly lower than the original label values.

In making the announcement today, Nair again emphasized that the variability of on-road fuel economy is greater for hybrids than for conventional vehicles. Relatively small differences in driver behavior and driving conditions can have a significant effect on the degree to which a hybrid’s gasoline engine is used for propulsion, which affects fuel efficiency. That may lead to future changes in testing protocols, Nair suggested.

One of the factors behind the 2013 C-MAX fuel economy issue, Nair said, was the EPA’s General Label rule. Developed in 1977, EPA label regulations allow, but do not require, vehicles with the same engine, transmission and weight class to use the same fuel economy label value data, since, historically, such vehicle families achieve nearly identical fuel economy performance. Under the rule, Nair said, the highest volume vehicle configuration is the one used to generate the fuel economy label.

Ford based the 2013 Ford C-Max label on testing of the related Ford Fusion hybrid, which has the same engine, transmission and test weight as allowed under EPA regulations—and is the higher volume configuration. It is also a sedan, and the C-MAX is a crossover-style vehicle. EPA’s evaluation found that the C-MAX’s different aerodynamic characteristics resulted in a significant difference in fuel economy from the Fusion hybrid.

For the vast majority of vehicles this approach would have yielded a more accurate label value for the car, EPA noted, agreeing that the hybrids are more sensitive to small design differences than conventional vehicles.

To date, most high-efficiency hybrids have been used in a single vehicle design and therefore do not have this issue, EPA added. The Ford hybrid family is one of two examples in the industry where advanced technology vehicles with the same engine, transmission and hybrid components are used across multiple vehicle designs. EPA regulations allow but do not require automakers to generate a label for each design in this circumstance. With the new Ford C-Max label, each vehicle design within the two high-efficiency hybrid families now has its own label.

Ford is standing by the original 47 mpg labeling for the Fusion Hybrid.

As an interesting side-note, the two plug-in hybrids—the C-MAX Energi and the Fusion Energi—were also labeled under the General Rule, Nair said. But in this case, the C-MAX Energi is the higher-volume configuration, and so became the basis for the label for the Fusion Energi. If tested and labeled separately, the Fusion Energi might turn in higher fuel economy numbers, Nair said.

Looking forward, EPA expects to see greater use of common high efficiency systems across multiple vehicles by manufacturers in order to improve quality and reduce manufacturing costs. EPA says it will be working with consumer advocates, environmental organizations and auto manufacturers, to propose revised fuel economy labeling regulations to ensure that consumers are consistently given the accurate fuel economy information.


Dave R

You can guarantee that Ford knows exactly what the C-MAX would score on the EPA test, but intentionally neglected to use those numbers and instead opt for the more favorable label they are technically allowed to use under the "General Label" rule.

Personally, I think the General Label rule should be abolished and different trim lines of the same vehicle should be required to have been run under their own EPA test when there is a change that is likely to affect fuel efficiency, namely wheel/tire size changes (many vehicles come with larger wheel/tire options which negatively affect fuel economy) and any body style changes (a sedan / hatchback is not likely to get the same fuel economy, either).

Steve Travis

Not good enough. Here's the reality check:

At, 256 Ford C-max were sampled and averaged 40.2 MPG. That is still very low compared to the NEW combined rating of 43 MPG.

In contrast, 342 Pius V's were sampled and averaged 43 MPG, while its rated combined fuel economy is 42 MPG.

If Toyota is to use the FORD way of fuel economy rating, then the Prius V should have a combined fuel economy of 46 MPG.

In short, Ford hyped up (lied about) their fuel economy rating while Toyota underestimated theirs.


And they are less than 10% apart, and the Ford has much better performance.


All of these vehicles are subject to how they are driven. The Prius is relatively low powered and probably not bought much by people that are going to drive it hard. However, I did read a report where someone took a Prius to a track and flogged it as hard as it could be flogged. They then took out a BMW and matched the track time. Lo and behold, they got about the same mileage. The 2014 Corvette will have a 30 mpg highway rating which you can probably achieve by careful driving but with 450 hp to play with, you will easily be able to push it down into single digit range.

Nick Lyons

We considered a C-Max, took the test drive and liked driving it. I was not impressed with the lack of a flat load floor, absence of any kind of spare tire, cheap-looking seat fabric and confusing electronics. The real-world fuel economy reports turned us off for good. We mostly drive highway miles, and for the price we may as well get a Honda Accord and get around the same mileage in a much nicer car.

Kit P

"and for the price we may as well get a Honda Accord "

Is a Civic not a nice car?

Nick Lyons

Civic is OK, but Accord has newer power train and highway mileage is just as good. Also, my sons are tall and very tall, and back seat leg room is a consideration.

Kit P


“back seat leg room is a consideration.”

What a good father! Your have to love the justification people have for getting snookered by car dealers. Nick you might want to take a skeptic with you when you go car shopping. First for a few thousand more you do not get more leg room. Second thing is when boys are getting tall it will not be long until you are riding in the back seat of their car.

How much leg room is there in the back seat of our new daughter-in-law Yaris? Not enough!

Envy is a terrible thing. The first time I heard of Accord envy was when I was driving an '84, ¾ Ton Suburban that we bought new to pull the trailer we lived in every time we moved. I was shocked when someone from our new church in California expressed Suburban envy. Back then they were UVs. Very good at hauling plywood if you are building your own house.

My point here is not that the Accord is not a nice car like so many others. My point is that since there have been cars, there are car makers who make more money by selling cars that are not that much nicer.

Timothy Gulden

Why Ford C-Max Hybrids are getting low MPGs analysis.

I have posted my report here:

My math substantiates my test condition findings.  Should I have made a mathematical error, please let me know.  If I hear nothing then I can assume it must be correct.  I reiterate, the C Max should be getting around 61 mpg at 60 mph...the math proves it.  Ford...if your reading this...please lower my RPMs in the next firmware release!  I will also volunteer to test your beta version for free.  Thanks in advance!

Nicholas Steblay

I own a C-Max and have driven it for the last year. My yearly average is 40.2 MPG. Mileage varies greatly depending on the time of year - I live in Minnesota. During the warmer months I was averaging 47+ MPG. It's the colder weather that impacts MPG the most. In the cold of the winter I was averaging only 35 MPG. The C-Max is dependent on what they call EV mode to achieve high mileage. EV mode is when the car is running solely using the electric motor. The C-Max can do this up to 85 MPH. In the winter the engine needs to run more often to keep the car warm. The less EV mode the worse the mileage. I believe Ford presented realistic EPA estimates based on 70 degree testing which I found to be accurate. The EPA should change the tests to require testing across a broad range of temperatures.

Nicholas Steblay

I should also mention I really like the car. I also own a Honda CR-V. The C-Max rides like a cross-over even though it is small. The C-Max is my commuter car and does its job very well. I average about 24 MPG with the Honda. I'm saving some decent money driving the C-Max at 40+ for a yearly average and haven't sacrificed comfort or ride qualities. I'm a big Honda fan having owned Civics, Accords and CR-Vs from the late 80's and will probably continue. I find the C-Max to be very comparable to my Honda experiences. I test drove the Prius at the dealership and as a rental from Hertz and chose the C-Max due to significantly more power, better visibility, and a more comfortable ride. I am very happy with my purchase and will driving the "Cardis" (named by my kids after the Dr. Who Tardis) for several years to come.

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