WATCH: 2022 Jeep® Grand Wagoneer Series III Highway MPG Test!

I recently had the opportunity to spend a week with the all-new 2022 Jeep® Grand Wagoneer Series III, the brand’s entry into the ultra-competitive full-size body-on-frame SUV segment. As part of our testing, we put the Grand Wagoneer through our highway MPG loop, a 109 mile (174 kilometer) loop at 70 MPH (112 KM/H), to see whether we could meet or exceed the Environmental Protection Agency (EPA) fuel economy number for the large SUV.

Grand Wagoneer Vs. Competition –

All Grand Wagoneer models currently come equipped with the 6.4-liter HEMI V8 which is mated to an 8-speed TorqueFlite^® automatic transmission offering a wide spread of gear ratios. The big HEMI delivers 471 horsepower and 455 lb.-ft. of torque. All Grand Wagoneers come standard with four-wheel-drive (4×4) and are EPA rated at 13 MPG city, 18 MPG highway, and 15 MPG combined. 

Cadillac’s Escalade is powered by the 6.2-liter V8 mated to a 10-speed automatic transmission. With 4×4 it is rated at 14 MPG city, 19 MPG highway, and 16 MPG combined. Lincoln, on the other hand, took a different approach. While naturally aspirated V8s power both the Jeep and Cadillac gasoline offerings, the Navigator offers a twin-turbocharged 3.5-liter V6. The powertrain carries an EPA rating of 16 MPG city, 21 MPG highway, and 18 MPG combined.  While both the Grand Wagoneer and Escalade require premium fuel, the Navigator can be run on regular 87 octane but does sacrifice some engine performance on lower octane fuels.

It also needs to be noted for those looking for the ultimate fuel efficiency, Cadillac does offer the Escalade with the 3.0-liter Duramax inline-six turbodiesel. Opting for this powertrain gives the Escalade a class-leading EPA MPG rating of 20 MPG city, 26 MPG highway, and 22 MPG combined on those models equipped with 4×4.

Our Test –

To ensure accuracy in our test, we use the same gas station and same pump for the initial fill and fill up after we run the highway loop. We run the two-click method, waiting 30 seconds after the pump clicks off and then pump again until the fuel pump clicks off a second time. We reset the vehicle’s trip odometer and hand calculate all the numbers at the end to ensure accuracy. 

There is a roughly 1-mile drive from the gas station to the highway. Once on the highway, we set the cruise control at 70 MPH and do our best to maintain that speed throughout the trip. Of course, traffic, the turnaround point, and the fact that we have 1 mile each way between the gas station and highway make it impossible to average 70 MPH for the test duration. We do our best to keep it as close as possible. 

The Result –

At the end of our test, the Grand Wagoneers trip odometer showed 174.4 km (109 miles) traveled. The trip screen also showed an economy rating of 12.3 liters/100km (19 MPG). Upon hand calculating the numbers, we did better than the trip odometer showed. We averaged 11.8 liters/100km or 20 MPG during our test, beating the EPA estimate by 2 MPG. 

Overall, it was very impressive how the Grand Wagoneer handled our highway MPG test. It was extremely comfortable, quiet, and achieved good real-world MPG for a vehicle of this size. Make sure to check out the video above for the entire test.

Also, make sure to check out our 0 to 60 MPH test and the Grand Wagoneer easter eggs. Stay tuned to MoparInsiders for all the latest news and information, along with the entire Grand Wagoneer review, coming soon. 

For those who are current Wagoneer/Grand Wagoneer owners or who are looking at purchasing one, be sure to visit our dedicated owner’s website, WagoneerForums.org. There you can talk about the latest news, information, and rumors, as well as, connect to other owners and even Wagoneer Client Services.