Curious about how to get better gas mileage? This article outlines technologies to look for in modern vehicles that will help you do just that.
It’s a paradoxical world we American drivers live in when it comes to the discussion around how to get better gas mileage. See the 10 vehicles on this list of most fuel-efficient cars? They’re all mid-size or smaller cars, which is of course the best place to start when it comes to stretching a gallon of gas due to their lighter weight. And yet, giant SUVs and full-size pickups dominate the landscape with some automakers abandoning cars altogether. I could pull my hair out and rant about this all day, but I digress. We are here to discuss a variety of ways that modern vehicles have increased their fuel economy, which is a pressing issue given current gas prices. Let’s start with the aforementioned vehicle weight.
Up until 20-odd years ago, most vehicles were built with steel due to its strength, ductility and abundance. With the march of time comes an associated march in technology progress, including new vehicle construction materials. Per the U.S. Department of Energy, a 10% reduction in vehicle weight can lead to an 8% improvement in fuel economy. So, it’s unsurprising automakers have been actively pursuing alternatives to steel on the assembly line.
Ford made headlines a few years back by announcing their flagship F-150 would be almost entirely made from aluminum. It was said to trim a whopping 700 pounds in curb weight. Carbon fiber is another strong but lightweight composite – it can reduce overall weight by 50-70%. It is typically reserved for more exotic applications like the wheels on Mustang GT350R or Alfa Romeo 4C chassis as it is relatively expensive. However, carbon fiber has started to trickle down into more mainstream applications like the cargo bed on a GMC Sierra.
In the past, turbochargers were used mainly on niche performance cars to deliver big-time power gains. Today, they are spread throughout the automotive landscape, from econo-boxes to pickup trucks. You can read up on the details of how a turbocharger works here, but basically, they force more air into the combustion process than the engine could inhale on its own. This reduces the amount of work done by the engine to produce more power, which bumps up efficiency. Turbos also allow for use of a smaller displacement engine, that is less thirsty, while typically delivering more power when needed, versus a naturally aspirated counterpart.
As an example, a base 2015 VW Jetta came with a naturally aspirated 2.0-liter four-cylinder motor that made 115 hp and 125 lb-ft of torque. EPA fuel economy estimates rate this older Jetta at 22 mpg in city driving and 33 on the highway. A brand-new base Jetta features a smaller, 1.5-liter inline-4 that pairs with a turbo to generate 158 horses and 184 torques. All while achieving city and highway fuel economy of 31 and 41 mpg, respectively.
The CVT is like an automatic transmission in that the driver has no input on gear selection, but utterly different in that it offers infinite gear ratios. Two cone-shaped pulleys, connected by a flexible belt, move independently to constantly vary the diameter of that flexible belts’ path. One pulley is connected to the engine and the other to the wheels, so the relationship between engine speed and power to the wheels can be instantly modified based on power requirements.
That is in contrast to a manual or automatic transmission that needs to be shifted through gears to keep the engine in its optimal power band. Along with cutting out this mechanical inefficiency of a traditional transmission, a CVT is typically lighter to boot. There was a time when a stick shift provided the best fuel economy, but no more. A 2022 Honda Accord with the turbocharged 1.5L four-pot and CVT earns 30 mpg in the city and 38 on the highway. Just two years earlier, the same car with a 6-speed manual was rated for 26/35 mpg in city/highway driving.
Most commonly seen in V8-powered pickup trucks, cylinder deactivation works just like it sounds. Four of the eight cylinders are taken out of use under light load conditions like cruising on the highway, with all eight fired up when you need to accelerate, for example. Interestingly, the efficiency comes from a reduction in pumping losses, not simply using less fuel since the same amount of power is still produced. You’ll see this technology in use on Chevy pickups listed as Active Fuel Management. Chrysler calls it the Multi-Displacement System and fits it to their Ram pickup series, noting it improves fuel economy by up to 20% when equipped.
Hybrid-powered vehicles are perhaps the most striking example of how to get better gas mileage. By blending a battery-powered electric motor with an internal combustion engine (ICE), you have a best-of-both-worlds scenario. The electric motor powers the car around town where the ICE is not very efficient. Meanwhile, the ICE can be of a smaller displacement than a conventional counterpart since it has the electric motor assisting. Plus, since it runs on gasoline there is no plug-in charging, and accompanying range anxiety, involved.
You can currently buy a Toyota Camry in traditional ICE configuration or as a hybrid. The standard version achieves 28 mpg in the city and 39 on the highway, which are solid figures. However, in hybrid form, those numbers spike to 51 and 53 mpg, in city and highway driving. When you combine that with the tips on improving mileage outlined here, you can seriously stretch a tank of gas, but be sure to read this article on why you don’t want to stretch it too far.