If you're looking at Mazda's big three-row SUV, the cx90 gas mileage is probably one of the first things on your mind, especially since this is the biggest vehicle they've ever put on the road. We're used to Mazdas being zippy and relatively light, but the CX-90 is a different beast entirely. It's heavy, it's luxurious, and it's meant to haul a lot of people. Naturally, that makes a lot of us wonder if we're going to be spending half our lives at the gas station.
The interesting thing about the CX-90 is that Mazda didn't just throw a thirsty V8 in there and call it a day. Instead, they went with some pretty high-tech powertrain options, including a brand-new inline-six and a plug-in hybrid. But as anyone who's ever owned a car knows, what's printed on the window sticker and what you actually see on your dashboard after a week of commuting can be two very different things.
Breaking Down the Inline-Six Numbers
The base engine in this SUV is a 3.3-liter turbocharged inline-six. Now, usually, when you hear "six-cylinder turbo" and "large SUV" in the same sentence, you assume the fuel economy is going to be pretty rough. Surprisingly, that's not really the case here. Mazda added a 48-volt mild hybrid system to this engine, which is basically a small electric motor that helps out with the heavy lifting when you're starting from a stop.
For the standard 280-horsepower version, you're looking at an EPA-estimated cx90 gas mileage of around 24 mpg in the city and 28 mpg on the highway. That's actually really impressive for a vehicle this size. If you opt for the high-output version (the one that pumps out 340 horsepower), the numbers stay almost exactly the same, which feels like a bit of a magic trick. Usually, more power equals more fuel, but Mazda seems to have tuned this thing for efficiency.
In real-world driving, most people find that the highway numbers are pretty achievable if you aren't driving like a race car driver. If you're cruising at 70 mph with the cruise control on, hitting 27 or 28 mpg is totally doable. However, the city mileage is where things get a bit more volatile. If you live somewhere with stop-and-go traffic every three blocks, don't be shocked if that 24 mpg drops closer to 20 or 21.
The PHEV Factor: Is it Actually Better?
Then there's the CX-90 PHEV, which is the plug-in hybrid version. This one is a bit of a polarizing choice for some people. On paper, it looks amazing because you get about 26 miles of all-electric range. If your commute is short, you could theoretically go weeks without using a drop of gas.
But here's the kicker: once that battery runs out, you're basically hauling around a heavy battery pack with a four-cylinder engine. When the battery is "depleted" (it never actually hits zero, but it stops acting as a pure EV), the cx90 gas mileage sits at around 25 mpg combined.
Is the PHEV worth it for the mileage alone? It really depends on how you charge it. If you have a charger at home and your daily errands are under 25 miles, you'll see incredible "fuel economy" because you aren't using the engine. But if you're doing 200-mile road trips every weekend, the inline-six might actually be the more pleasant (and similarly efficient) experience.
Why the Transmission Matters for Your Wallet
One thing that people don't talk about enough when discussing cx90 gas mileage is the transmission. Mazda didn't use a traditional torque converter automatic. Instead, they developed an eight-speed multi-plate wet clutch transmission.
The reason this matters for fuel is that it's more direct and efficient than a standard automatic. There's less energy lost in the transfer from the engine to the wheels. It can feel a little different—sometimes a bit "mechanical" at low speeds—but it's one of the main reasons a big SUV like this can even touch 28 mpg on the highway. It keeps the revs low and makes sure the engine isn't working harder than it needs to.
Real-World Driving: What Owners Are Saying
If you spend any time on owner forums, you'll see a wide range of reports regarding the cx90 gas mileage. Some people are absolutely thrilled, reporting that they've managed to squeeze 30 mpg out of the inline-six on long highway hauls. These are usually the folks who use the "Eco" mode and keep a steady foot.
On the flip side, you'll find owners who are frustrated that they're only seeing 19 or 20 mpg. Usually, these are people living in hilly areas or those who have a bit of a lead foot. The CX-90 is fun to drive—it handles better than almost any other three-row SUV—so the temptation to hit the gas and feel that turbo kick in is real. But if you give in to that temptation, your fuel economy is going to take a nose-dive.
Does Premium Gas Make a Difference?
This is a common question for Mazda owners. For the Turbo S models, Mazda says you need premium fuel to get the full 340 horsepower. However, you can run it on regular 87 octane. The computer just adjusts the timing, and you end up with about 319 horsepower instead.
Does it affect the cx90 gas mileage, though? Not significantly. While higher octane can sometimes lead to slightly better efficiency in high-compression engines, most drivers won't notice a difference in their MPG between regular and premium. You'll mostly just notice it in your wallet at the pump and a slight dip in passing power on the freeway.
How it Compares to the Competition
To really understand if the cx90 gas mileage is good, you have to look at what else is out there.
- Honda Pilot: This is the old-school rival. It uses a tried-and-true V6, but it usually averages around 21 or 22 mpg combined. The Mazda beats it pretty handily.
- Toyota Grand Highlander Hybrid: This is the efficiency king of the segment. The Toyota hybrid can get up to 36 mpg combined. If fuel economy is your only priority, the Toyota wins. However, the Mazda is significantly more "premium" feeling and way more fun to drive.
- Kia Telluride: Like the Pilot, the Telluride sticks to a V6 and usually hovers around 20-22 mpg in the real world.
So, the CX-90 sits in this nice middle ground. It's more efficient than the traditional gas-only V6 SUVs, but it doesn't quite hit the crazy high numbers of the dedicated Toyota hybrids. For many people, that's a fair trade-off for having a car that doesn't feel like a boring appliance.
Tips for Stretching Your Tank
If you end up buying one and want to maximize your cx90 gas mileage, there are a few things you can do. First, use the "Normal" or "Eco" modes. The "Sport" mode is great for winding roads, but it holds gears longer, which absolutely kills your fuel economy.
Second, pay attention to the i-Stop system. Mazda's stop-start tech is actually pretty smooth compared to some other brands. Letting the engine shut off at red lights might seem annoying, but in heavy city traffic, it really does save a measurable amount of gas over the course of a month.
Finally, keep an eye on your tire pressure. It sounds like "dad advice," but because the CX-90 is a heavy vehicle, under-inflated tires create a lot of drag. Keeping them at the recommended PSI ensures you aren't fighting against your own car just to keep it moving.
Final Thoughts on Fuel Efficiency
At the end of the day, the cx90 gas mileage is impressive for what the vehicle is. You're getting a massive, three-row luxury-leaning SUV that can actually get high-20s on the highway. That would have been unheard of ten years ago.
If you're coming from a smaller sedan or a compact crossover, you're going to notice you're spending more on gas. There's no way around that—physics is physics. But if you're moving from an older Tahoe, Explorer, or even an older CX-9, the efficiency gains in the CX-90 are going to be a breath of fresh air. It's a sophisticated machine that manages to balance power and thirst better than most of its peers. Just remember that your right foot has more control over the MPG than the EPA does!