How to Improve Gas Mileage on 6.4 Hemi? (Solved)

In today’s world, cars are one of the most important things in life. Whatever the need, a car has a lot of roles to play in making it comfortable and fast. As long as we take proper care of our cars, the cars provide proper service.

We have many ways to increase vehicle performance or mileage. Car companies or pro mechanics advise increasing the car’s gas mileage. One of the most popular modern engines is the 6.4 Hemi.

A 6.4 Hemi engine will keep you in service for a long time if you take proper care of it. There are certain mechanisms by which you can increase the performance and gas mileage of this engine. In this article, we will discuss that topic so stay tuned. 

What Is a 6.4 Hemi?

For the convenience of everyone, we will know the details about 6.4 Hemi. The 6.4 Hemi is a 6.4 liter Hemi engine. Its manufacturer is Chrysler. The reason behind the name “Hemi” is that it is an engine that has a hemispherical combustion chamber. 

It surpasses another popular engine 5.7 L Hemi in terms of design but not in terms of performance. The 6.4 Hemi engine was first used on a truck called Dodge Ram and was launched in 2009. 

In addition to this vehicle, the engine was also used in cars like Charger, Challenger, Grand Cherokee, Durango, etc. This 6.4 Hemi engine was later used in Jeep Grand Cherokee SRT8 and SRT Viper vehicles.

How to Improve Gas Mileage on 6.4 Hemi?

The engine of a car should be taken to the auto shop for a regular checkup. But pause before you do the same with your Hemi. There are some things you can consider first.

Several factors play a role in enhancing the overall performance of an engine, all of which are extremely important. None of them should be taken lightly. However, we will now discuss some of the factors that are required to increase the gas mileage of 6.4 Hemi.

Tips to Improve Gas Mileage on 6.4 Hemi infographic

Check the Engine

It is possible to improve the gas mileage by checking the engine of the car at regular intervals. An engine has different parts and all of them need to be tested. You can also change the spark plug while testing to provide improved power and reduce pressure on the engine.

Many people are lazy and do not check the engine of their car. This can lead to engine problems such as reduced gas mileage. You need to tune up the engine to make it run smoothly.

Engine Oil

The performance of the engine largely depends on the engine oil. Whether you are using the right brand of oil or changing the oil regularly is very important. These factors greatly affect the engine’s gas mileage.

Engine oil reduces the friction of the internal parts of the engine and helps them to run smoothly. This reduces the pressure on the engine and saves fuel. Therefore, if you do not pay enough attention to the engine oil, the engine will not give the desired mileage and will be damaged gradually.

What can be done then? You should change the engine oil every 4800 km or 3000 miles. Use engine oil recommended by the company considering the quality aspect. If you can’t decide on your own, consult an expert. 

Clean the Air Filter

The function of an air filter is to provide clean air so that the engine can run smoothly. If the filter does not work or there is a problem with it, dust or debris can enter the engine and ruin it. 

Then the gas mileage will be reduced and the engine will be defective. To check the filter, hold it in front of the light and check how much light you can see in the opposite direction. Clean the filter as needed.

Observe the Condition of the Tires

Yes, the condition of your car’s tires also affects the engine mileage. If the tires wear out, there is more pressure on the engine. This is why the engine consumes more fuel and increases your costs.

There should be enough air inside the tire. If the tires do not have the required amount of air, the engine drags more and blows more gas. If this problem is not solved, the car may get stuck on the road or the tire may burst. So check the tires every time you go out.

Drive the Car Regularly

It is better to use any electronic and engine-driven device regularly, not just cars. In the case of vehicles, regular driving and testing under different conditions are very important. If you drive regularly on highways and off-road, the engine will be more efficient and will save fuel. 

Conversely, if you leave the car, the parts will rust and the engine will lose performance. It has been proven by all auto companies that if the car is left lazy, its mileage decreases significantly. So drive your car as much as possible and it will have a positive effect on the engine. 


Each vehicle has a certain level of carrying the load. When you overload the car, it will burn more fuel. Also, overloading puts pressure on the wheels and causes rapid corrosion. So try to keep the weight of the car as low as possible to increase the gas mileage.

Efficient and Safe Driving

If you want to make the car last longer then you have to drive carefully and efficiently. Doing so will reduce the pressure on the car and increase the gas mileage. 

You can’t do hard brake and accelerate, you have to keep the engine off when idling, you can’t take the car out of speed, and so on. If you adhere to these conditions then of course the mileage of the car will increase and the performance of the Hemi engine will increase.


We try as much as we can to increase our car’s gas mileage but to no avail. It is difficult for most drivers to follow the steps to increase gas mileage. So in this article, we have presented in detail how you can increase the gas mileage of your 6.4 Hemi. 

These methods are very effective and simple. So if you are a little cautious and follow our advice you can benefit economically by increasing your 6.4 Hemi gas mileage.

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William Baldwin

This Is William Baldwin, The Founder & Managing Editor of this website. Me and my team share automotive tips, tricks, and news

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Talha Atta

Talha Atta, a Mechanical Engineer and experienced technical content writer and editor at with a passion for the automotive industry.