Do Lift Kits Affect Miles Per Gallon?
Some trucks aren’t friendly on the wallet. Their fuel economy won’t be the best, so when you modify them, it’s a bit of a bummer to see the miles per gallon drop. Since one of the most common customizations is a suspension lift kit, it’s common to ask yourself if it will affect your wallet. Let’s find out in this article.
Do lift kits affect miles per gallon?
Yes, almost all lift kits affect your fuel economy in some way. More complex systems can decrease fuel performance since they are heavy and increase wind resistance. Some options have minimum impact on your truck’s miles per gallon. Generally speaking, any modification you do to your ride will affect its performance.
There are plenty of lift kits out there, and each affects your truck differently. The overall goal is to increase the distance between the vehicle’s frame and the ground. This helps in avoiding obstacles when you navigate through challenging terrain. There are also aesthetic reasons for doing so.
The most basic kits consist only of spacers that go between the frame and the suspension, therefore lifting the body 1″ or 2″. Though these add weight, there’s little impact on fuel economy.
The larger kits include aftermarket components like control arms, shocks, springs, and bushings. Some of these might be heavier than the factory alternatives. We’ll see later how these modifications can affect the fuel economy.
It’s hard to determine how many miles per gallon you will lose if you install a lift kit. But, there’s one thing for sure. No equipment is likely to increase your fuel economy. So, let’s discuss how exactly do lift kits affect your truck’s fuel performance.
How does lifting affect fuel economy?
There are several ways lift kits can affect your truck fuel economy. First of all, there’s weight. While adding spacers might not add many pounds, an entire suspension kit might tip the scales.
The truck has to carry all this additional weight. It’s common knowledge that a heavier vehicle consumes more fuel.
But, keep in mind that not all kits are heavier. Some more expensive options actually have lighter and more robust components.
There’s one aspect that’s unavoidable with the lift kit. The fact is, the higher your truck is, the more wind resistance it generates.
Your truck leaves the factory with a determined drag coefficient. This number represents the resistance the vehicle puts on the air around it as it moves through it.
When you lift your truck, the vehicle has more surface that comes in contact with the air. Therefore, it produces more drag, which forces the engine to work harder to move at the same speed as before. That’s why sportscars and trucks (like the 90’s Ford Lightning) are lower to the ground.
Now, it might seem that your vehicle is traveling at the same speed. And, most likely, it hasn’t lost a lot. But, all resistance adds up, especially on the highway. While it’s hard to calculate how much fuel economy will drop, it’s safe to say you will lose some miles per gallon.
On the same line, not all kits will affect performance equally. A leveling kit or a 1″ lift kit changes the resistance very little.
On the other hand, a 4-inch modification will increase the area of friction considerably.
But, the lift kit isn’t the most crucial reason why you could lose miles per gallon. It’s what comes with it.
How do bigger tires affect miles per gallon?
Let’s face it, if you’re going to lift your truck, you will install bigger tires. That’s why a lot of people modify their trucks. Otherwise, it would just look weird with a raised body and thin tires.
And it’s these tires that actually affect your fuel performance the most. The bigger the tire, the larger its diameter. So, the engine has to work harder to move them.
Also, since they’re wider, the area of contact between the tire and the surface increases. This translates to more friction, therefore requiring more power from the engine. All these factors increase fuel consumption.
Finally, there’s the most logical aspect. Bigger tires are heavier. So, the more weight you put into your truck, the more fuel you will consume.
In fact, the EPA estimates that for every 100 pounds of additional weight, a vehicle can lose between 1% or 2% of fuel economy. So, if all these modifications are heavier than the original components, then it’s almost sure that you will lose miles per gallon.
But that’s not all. There are other reasons why a lift kit could be affecting your wallet.
How lift kits affect other driving aspects
When you lift your truck, the angles between the transmission and wheels change. So, the shafts that connect these two ends are rotating at a different position than the manufacturer had intended.
This variation in angle can cause friction between the shaft and the body. Any additional rubbing will wear out the components quicker.
It will also increase the fuel the engine consumes to overcome that friction.
Then, there’s braking. If you fit bigger tires but stick with the original brakes, they might not have the same stopping power. Remember that the diameter is now bigger, which means you need more force to slow the tires down.
Since a modified truck can be heavier, and if the brakes are still original, slowing down is more challenging. Plus, it’s higher off the ground, so momentum can change. In fact, if you’re driving a lifted vehicle and you stop suddenly, you might feel the cabin move more.
Finally, there’s the readout. The speedometer and tachometer come with a determined calibration from the factory. The manufacturer calculated how fast a truck goes and how much distance it covers with determined tire sizes.
When you fit bigger tires, the tachometer will rotate at a slower pace. So, while in reality, you might have traveled ten miles, your dash might display fewer miles. The same happens with speed.
The bigger the tire, the fewer rotations, so the speed will be less. Will it be enough to deceive you into a speeding ticket? Not likely, but it will alter your readout.
Of course, the same applies to a smaller tire. In fact, if you fit a tire with less profile, then the vehicle will perceive more rotations. Therefore, the speed is higher than indicated, and there’s more distance traveled.
The best way to sort this is by recalibrating the instruments, though not all speedometers and tachometers can be adjusted. For those who are obsessed with numbers and precision, it’s worth looking into it.
Can you do anything to improve miles per gallon on a lifted truck?
You drive a modified truck doesn’t mean you necessarily love spending money and time at the fuel station. So, let’s find out some of the things you can do to help improve the miles per gallon on a lifted vehicle.
The first strategy is a light foot. As always, driving with low revs and not forcing the engine will do wonders for your miles per gallon.
Then, there’s weight. The less you carry in your truck, the more fuel you’re going to save. So, try to keep it as empty as possible.
Finally, the tires play a crucial part. If you’re not offroading, then you might not have to use your all-terrain tires constantly. You can switch them for standard tires while you drive in the city. The drawbacks to this strategy are that your truck might look weird, with smaller tires, and that you have to change them constantly.
Closing thoughts
This article aimed to answer a general question. Do lift kits affect the fuel economy of your truck? The answer is yes. But not for the reasons you might think.
In fact, there are a lot of reasons why the miles per gallon are less on a lifted truck. The kind of lift kit you choose is vital.
Basic modifications like leveling kits and 1″ lifts aren’t that heavy. The fuel economy with these will not change significantly.
But, when you get into lift kits that increase 3″ or 4″, then you’re increasing your truck’s drag coefficient. This is the resistance it puts against the air that surrounds it when it’s driving at speed.
Because your truck is higher, then more surface comes in contact with the air, therefore slowing it down.
But there’s another reason that’s not entirely dependent on the lift kit, but rather what you do afterward. When you raise your car, chances are you will also introduce bigger tires.
Bigger tires are heavier, wider, and taller. All these factors translate to the engine needing more energy to move them. Therefore, you should expect to have fewer miles per gallon if you’ve fitted these.
There are some strategies you can use to improve fuel economy, even on lifted cars. They revolve around driving economically and removing weight from your vehicle. In the end, any modification will affect your vehicle’s performance. Hopefully, this article teaches how to control that so that your wallet doesn’t suffer much.