Full-size SUVs are popular because of their versatility, as well as their safety and cargo space. They’re also expensive, sometimes insanely so, and those in the market for a large SUV may find themselves looking for a used SUV instead of new. This is especially true in the current automotive climate, where both new and SUVs are increasingly difficult to find. Yet if you’re trying to save some cash, you’re probably also going to want to save money on gas, and that’s not something full-size SUVs are good at. While you could shop for the used SUV with the best gas mileage, you should also steer clear of the SUVs with the worst gas mileage.

To determine which used SUVs are worst on gas, Car and Driver tested them on a 200-mile out-and-back stretch of highway. In fact, they tested a whole bunch of vehicles, though several used SUVs made the list of the worst SUVs on gas. Car and Driver tried to maintain 75 mph to keep things as fair as possible. These used SUVs are far from the best on gas mileage, they’re the worst.

The 2018 Toyota Sequoia is far from one of the best SUVs on gas

In fact, according to Car and Driver, the 2018 Toyota Sequoia is one of the worst full-size SUVs on gas. That’s because the 2018 Toyota Sequoia has a 5.7-liter 381 hp V8 engine that basically eats gas like candy. Its the same engine as the Toyota Tundra, and Car and Driver notes that this is likely how it found itself on a list made up mostly of large pickup trucks. Car and Driver found that the 2018 Toyota Sequoia got 16 mpg in their highway test, which is pretty low, even for a large SUV. It’s even worse than its EPA-estimated range of 17 mpg on the highway.

The 2019 Mercedes-Benz G550 is a luxury SUV that is far from being the best on gas

The 2019 Mercedes-Benz G-Class may be really nice, but it isn’t an SUV with the best gas mileage. No, the 2019 Mercedes-Benz G-Class only gets 15 mpg in Car and Driver’s tests. It has a 4.0-liter V8 engine and nine-speed automatic transmission. The 2019 G-Class was its first revamped G-Class in thirty years, and while many positive changes occurred with the 2019 model, fuel economy is even worse than the 2018 Toyota Sequoia.

The 2017 Mercedes-Benz AMG G63 isn’t going to save money on gas

These Reliable Used Luxury SUVs Are Still Going Strong, According to Consumer Reports

Fuel economy may not have been at the top of the list of priorities at Mercedes-Benz when they made the 2017 Mercedes-Benz AMG G63. If you’re buying this Mercedes, you may not be as worried about the cost as you are about the excess that an SUV only getting 15 mpg on the highway creates. That 15 mpg that Car and Driver found is slightly better than its EPA-estimated 14 mpg on the highway, which is very low.