If you're looking at buying a heavy-duty truck, the 6. 6 v8 gas mileage is probably main things you searched for, just after checking out the towing capacity. Let's be truthful: nobody buys a three-quarter-ton or one-ton truck because they will want to save cash at the pump motor. You buy it since you have stuff to advance, trailers to pull, or even a work that requires the frame that won't buckle under stress. But even in the event that you aren't planning on Prius-level efficiency, you still need to understand how often you'll be stopping intended for fuel and how very much it's likely to harm your wallet.
The 6. 6L gas engine, particularly the L8T found out in the newer Chevy Silverado and GMC Sierra 2500 and 3500 versions, was a big shift when it replaced the old 6. 0L. It's the beast of the engine, built for durability along with a cast-iron wedge, but it provides a reputation for being a little bit thirsty. If you're seeking to budget for a new rig, here is the lowdown on what that fuel economy actually looks like within the real world.
What the numbers look like around the dashboard
Whenever you appear at the windowpane sticker of the heavy-duty truck, you'll notice something annoying: the EPA doesn't actually require gasoline economy ratings regarding vehicles in this particular weight class. Because trucks have a GVWR (Gross Vehicle Excess weight Rating) over 8, 500 pounds, the don't have in order to put an official MPG estimate upon the sticker. This leaves a lot of buyers speculating.
From exactly what I've seen plus heard from dozens of owners, the 6. 6 v8 gas mileage usually settles in to a pretty predictable range. For a totally stock truck with no weight in the back, you're looking at about ten to 12 mpg within the city . If you've obtained a light foot plus you're cruising upon a flat freeway at 65 with, you might discover 14 to 16 mpg . If a person push it in order to 75 or eighty mph, though, that number will fall faster than the usual rock and roll. The wind level of resistance on these vehicles is massive, plus once you get into higher rates of speed, that big 6. 6L has in order to work significantly tougher to push most that air out of the way.
Why the city numbers are so low
Stop-and-go traffic is the particular natural enemy of the 6. 6L gas engine. It's a heavy engine sitting in the heavy truck, and getting that very much mass moving through a dead stop requires a lots of energy. Every time the sunshine turns green, the particular injectors are throwing fuel to get those thousands associated with pounds rolling.
If your daily commute involves a lot of traffic lighting or short journeys in which the engine doesn't even have time in order to reach operating temperatures, don't be surprised if your typical stays firmly in the single digits. It's not uncommon in order to see 8 or nine mpg if you're firmly driving inside a congested urban environment. It's just the nature of the beast.
The actuality of towing and hauling
Many people buying these types of trucks are carrying out it because these people have a trailer. Whether it's the horse trailer, a fifth-wheel camper, or a flatbed full associated with equipment, the 6. six v8 gas mileage is going to have a hit the second you hook upward.
When you're towing a moderate load—say, around 8, 000 to 10, 000 pounds—you can expect to see somewhere between 7 and 9 mpg . If you're pulling something even heavier or something along with the aerodynamics of a brick (like a tall vacation trailer), you might even see 5 or even 6 mpg when planning into a headwind or climbing the grade.
This might sound scary, but it's actually fairly comparable to the outdated 6. 0L plus even some associated with the older big block engines. The difference is that the new six. 6L has a lot more torque and strength, so it doesn't seem like it's having difficulties just as much, even when it's drinking just as much gas.
The transmission factor
One thing that really transformed the game for your 6. 6 v8 gas mileage was when GENERAL MOTORS finally paired the engine with the 10-speed Allison-branded transmission. Within the first few years (2020-2023), the gas 6. 6L was tied to a 6-speed automatic. While that 6-speed was tough, the gets between gears were huge, which often meant the engine had been screaming at higher RPMs or lugging at low types.
The 10-speed, which became standard for the gas engine in the 2024 models, helps keep the motor in its "sweet spot" more frequently. Although it doesn't magically turn the vehicle into an economy car, it will help with motorway cruising and can make towing a very much smoother experience. You might gain 0. 5 to 1 mpg overall with the 10-speed, but more significantly, the truck simply feels more able and less stretched.
Gas versus. Diesel: The best controversy
You can't talk about gas mileage without talking about the Duramax diesel. Yes, the diesel-powered can get better mileage—usually around 17-20 mpg on the highway and 10-12 mpg while towing . However, you possess to consider the "total cost of possession. "
The particular diesel engine is really a roughly $10, 000 upcharge upfront. After that you've got the higher cost of diesel fuel, DEF (Diesel Exhaust Fluid), even more expensive oil changes, and the looming fear of high-dollar repairs like injectors or emissions techniques in the future. For a lot of people, the 6. 6 v8 gas mileage is the fair trade-off regarding the simplicity and lower maintenance costs of a naturally aspirated gas engine. If you aren't towing heavy every single day, the gas engine often can make more financial sense over a 5-to-10-year period, even in the event that you're spending more at the gas station.
How mods affect your fuel economy
We all enjoy the way the heavy-duty truck looks with a ranking up kit and 35-inch mud tires, yet your wallet won't. If you determine to strengthen your truck, kiss that will 6. 6 v8 gas mileage goodbye. Adding bigger, heavier tires raises rolling resistance plus changes your efficient gear ratio. It's very common for owners to observe a 2-3 mpg drop just by switching in order to aggressive all-terrain or mud tires.
If you're worried about gas, stick to the stock tire size and a more highway-friendly stand pattern. Also, keep an eye on your tire pressure; running them as well low can pull your mileage lower further than you'd think.
Suggestions for squeezing out an extra kilometer per gallon
If you're stuck with the 6. 6 gas and need to try to enhance your numbers, there are a few things you may do. None of these will work miracles, but they add up over the long trip:
- Keep this under 70: These trucks have the aerodynamics of a garage door. Slowing down from 75 to 65 mph may sometimes net you an extra 2 mpg.
- Use cruise handle: Upon flat ground, the computer is more preferable at maintaining a steady accelerator than your foot is.
- Clear the bed: If you're hauling around hundreds of pounds of tools or scrap metal that a person don't need for that specific trip, take it out there. Weight is the particular enemy of effectiveness.
- Upkeep matters: Keep your air filter clean. A clogged filter makes typically the engine work harder to breathe, which can tank your own mileage.
Is the 6. 6L gas engine best for you?
At the particular end of the day, the 6. 6 v8 gas mileage is usually exactly what you'd expect from a heavy-duty workhorse. It's thirsty, it's effective, and it's dependable. If you're someone who does the lot of short trips, works in the trades, or even wants a truck that will is easy to maintain without the headaches of modern diesel-powered emissions systems, the trade-off in fuel economy is generally worth it.
You aren't buying this truck in order to win any green-energy awards. You're purchasing it to obtain the job completed. So long as you go into the purchase realizing that you'll likely be seeing 12 mpg on regular, you won't be disappointed. It's a solid, dependable engine that will probably outlast the entire body of the truck it's sitting in—you'll just get in order to know the people at your local gas station pretty well as you go along.