Ford · 2015
Flex FWD 3.5L 6-cyl
✓ EPA Verified
Regular Gasoline
Standard Sport Utility Vehicle 2WD
Front-Wheel Drive
City
18
MPG
Combined
20
MPG
Highway
25
MPG
Annual Fuel Cost
$2,200
Based on 15,000 miles/year · EPA estimates
vs avg gas vehicle
$50
more per year
Class Comparison — Standard Sport Utility Vehicle 2WD
Bottom 46%
Better than 46 out of 100 vehicles in its class for fuel efficiency.
This vehicle: 20 MPG
This vehicle
20 MPG
Class average
25 MPG
Class lowest
15 MPG
EPA Energy & Environment Scores
5
Energy Score
Out of 10
5
GHG Score
Out of 10
438 lbs
Annual CO₂
g/mile tailpipe CO₂
No
Start-Stop
Not equipped
Vehicle Specifications
Engine3.5L 6-cyl
TransmissionAutomatic (S6)
DriveFront-Wheel Drive
Fuel TypeRegular Gasoline
Vehicle ClassStandard Sport Utility Vehicle 2WD
Start-StopNo
EPA Vehicle ID35949

The 2015 Ford Flex FWD with the 3.5L V6 gets 20 MPG combined. While this isn’t a chart-topping figure, interior space, comfortable seating for up to seven, and a unique style are usually what families considering this distinctive, boxy wagon prioritize. Flex buyers need people-hauling capability and aren’t necessarily looking at hybrids or compact crossovers.

City and highway performance

The 2015 Ford Flex FWD 3.5L gets an EPA-estimated 18 MPG in the city and 25 MPG on the highway. The lower city number reflects the realities of stop-and-go traffic, where the Flex’s weight and the engine’s need to overcome inertia reduce efficiency. The highway figure is more respectable, thanks to the six-speed automatic transmission and relatively relaxed engine speeds at cruising speed. Expect the MPG to drop closer to the city figure if you frequently haul a full load of passengers and cargo on road trips.

Annual fuel cost

According to the EPA, the estimated annual fuel cost for the 2015 Ford Flex FWD 3.5L is $2,200. This calculation is based on driving 15,000 miles per year and using national average fuel prices. Your actual fuel costs will vary depending on your driving habits, the type of driving you do (city vs. highway), and where you live, as fuel prices fluctuate.

Real-world expectations

EPA estimates provide a baseline, but real-world fuel economy often differs. Some 2015 Ford Flex owners report slightly lower MPG numbers than the official figures, especially in mixed driving conditions. Aggressive driving, frequent short trips, and carrying heavy loads will all negatively impact fuel efficiency. However, drivers who accelerate smoothly and maintain consistent highway speeds may see numbers closer to the EPA’s estimates. The FLEX MPG across all years can also give you a sense of whether one model year could better suit your needs.

How it compares

The 20 MPG combined rating places the 2015 Ford Flex FWD 3.5L roughly in line with other large crossovers and SUVs of its era, but behind more modern and efficient options. For example, the 2015 Toyota Highlander with its 3.5L V6 and FWD achieves a slightly better 21 MPG combined. A 2015 Honda Pilot, another popular competitor, also manages around 20 MPG combined in its FWD configuration. The Flex’s appeal lies in its distinctive styling and generous cargo space, which set it apart from the more conservatively styled Highlander and Pilot. Buyers willing to sacrifice some space and third-row comfort might consider a Mazda CX-9, with the newer generations achieving significantly better fuel economy, but those vehicles won’t offer the same cavernous interior.

Tips to maximize efficiency

Gentle acceleration is key to saving fuel in the Flex. Avoid fast starts and try to anticipate traffic flow to minimize unnecessary braking and acceleration. The 3.5L V6 responds well to smooth, steady throttle input.

Regular maintenance, particularly ensuring proper tire inflation and a clean air filter, can have a noticeable impact on fuel economy. Low tire pressure increases rolling resistance, forcing the engine to work harder. A dirty air filter restricts airflow, reducing engine efficiency.

Minimize idling. Idling burns fuel without covering any distance. If you’re stopped for more than a minute, it’s generally more fuel-efficient to turn off the engine and restart it. This is especially true on cold starts.

Consider reducing your highway speed. While the Flex is comfortable at higher speeds, fuel economy decreases significantly above 65 mph due to increased aerodynamic drag. Slowing down just a few miles per hour can make a difference on long trips. Explore all Ford fuel economy data to compare the Flex with other models.