Efficient Strategies: How to Get 30 MPG with a Duramax

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We all know the Duramax engine’s main advances – the sheer power, torque, longevity, and reliability. But, what about fuel economy? Their fuel efficiency is around 15 miles per gallon. From there comes one of their most frequent questions – how to get 30 MPG with a Duramax.

There are a couple of ways to reduce money on fuel costs. You can tune the truck so it will have better fuel economy. The other way that can supplement the first is upgrading the exhaust system. Other factors are mainly connected with driving habits. You can feel the improvement in fuel economy if you avoid driving with the heavy foot. Also, city driving with a lot of idling will raise the average fuel consumption.

fuel mileage for a duramax diesel

We will dig deeper into the poor fuel economy problem and how to resolve it, so stay with us. By the end, you will know what your driving style can bring to the table and how to improve your truck to improve gas mileage.

Duramax Definition

The Duramax engine was created by General Motors and Isuzu back in 2001. These diesel engines are from then a favorite choice for light-duty trucks and vans. It is also a good choice for towing light to medium loads.

For over 20 years, these engines have developed through the generations. The engineers constantly listen to the drivers, resolve issues, and improve performance. Today, These engines are a mix of powerful and reliable engines with high emission standard ratings. 

Advantage of Duramax

This engine family is known for its high-power output and massive torque values. With proper tuning, these engines can get over 1000 hp. When you have an engine like that, you can drag race, tow whatever you want, or use it for cruising and highway driving.

One of the most favorite Duramax features is its durability and longevity. It is really hard to destroy these engines. Also, over the years, Duramax engines have developed a big market for all sorts of aftermarket and tuning parts. You can find any part for even the oldest generations of these engines.

Downside of Duramax

The price of these engines is their first downside. These engines, as new, can cost well over $10,000. That is significantly more when compared to a gasoline engine.

Although you can easily find all the parts for any Duramax engine, they tend to be not so cheap. Duramax demands proper maintenance and the use of high-quality parts, and that is fine. With better maintenance, your engine will last longer, and it will have improved fuel economy. The only thing is – can you afford it?

Every diesel truck has a common problem. It’s loud-sounding work. You cannot help that. Diesel engines are just loud. Some like the sound of diesel engines, while others cannot stand it. It is a question of personal preference. 

Diesel engines are not only louder than gasoline engines, but they also have a diesel particulate filter (DPF). Its job is to lower bad diesel emissions. With that, they are also taking a lot of money on maintenance. The DPF is expensive both to maintain and to replace. 

Pros

  • High-power output
  • Massive torque
  • Durability
  • Longevity
  • Uses DPF

Cons

  • Cost higher than a gasoline engine
  • Expensive parts of a Duramax engine

How Can a Duramax Engine Get 30 MPG?

Getting 30 MPG from a Duramax is a hard task, but with some work, it can happen. You will have to invest in some tuning and replacing old parts. Also, you will have to work on your driving style and avoid aggressive acceleration.

Replace Old Parts

Research on how the parts impact fuel usage. If you have problematic old parts that harm fuel consumption, replace them with new ones. They will bring new levels of performance and fuel usage into play.

Modify the Exhaust System

You can either modify or completely replace the exhaust system. It is a key part that helps in circulating the air to and from the engine. Upgraded or a new exhaust will not only improve performance, but you will see improvement in fuel economy. If you know something about car mechanics, you can do this yourself and avoid labor costs.

Adequate Fuel Utilization and Tuning

Find the best type of fuel for your engine. Some fuels offer better performance or better fuel mileage. Choose the right type and stick with it. It will take some time, but you will notice an improvement. It is also a good thing to consider tuning the engine. You will get the best results from new and improved fuel.

Change the Powertrain

For this, you will need assistance from a mechanic. Consult him about your specific type of engine. Different types of powertrain improvements help in reducing fuel consumption.

Altering the Cooling System

Your car’s cooling system does impact fuel consumption. The fuel pump moves the coolant fluid through the radiator and the engine. So, altering the fuel pump will help you get to the 30 MPG goal. Also, keep the radiator clear of any blockages and obstructions. Regularly check the thermostat and the lines of the cooling system. 

Invest In a New Engine System

Your engine might be too old and worn to allow you to reach a 30 MPG goal. The least you can do is replace or add the turbo. When you are at it, you can also see what other engine parts are worn and can be improved. This way you will increase engine power and raise miles-per-hour values.

Improve Transmission

If you have a 5-gear auto transmission, replace it with a 6-gear transmission. That will not only offer a comfier ride but will also save you lots of fuel. This is especially true when driving at a higher speed or on a highway.

Drive Shaft Adjustment

Altering a gear ratio is one of the ways to achieve excellent fuel economy. Replacing the drive shaft can reduce the gear ratio. You will not only get excellent fuel efficiency, but the truck will better accelerate.

Suspension System Alternation

Installing a custom lift kit will get you slightly improved fuel efficiency. But, besides that, your truck will have higher ground clearance. That will allow you to move freely off the road to a more adventurous ride.

Work on the Radiator

The radiators have a certain impact on fuel efficiency. If you have an older type of radiator, replacing it with a new one will bring better fuel consumption.

Altering Other Exterior Elements

You can install a bed cover or even remove the tailgate. But do not expect too much improvement in fuel efficiency coming from these external tweaks.

Trip Preparation In Advance

If you have several places to visit, plan the trip. Find the best routes and times. Try to avoid gridlock and unnecessary idling. Shorten your trip, but still get everything done. That will save you so many gallons of fuel in the long run.

Drive Slowly

Every normal human likes to press the accelerator pedal from time to time. To feel that power. But don’t overdo it. It will blow fuel consumption through the roof.

Check the tire pressure

If the tire pressure is too low or too high, it will raise the fuel consumption. Check the factory specification and follow them. You will not only improve efficiency in fuel consumption, but you will have a comfier ride.

Lower air conditioner use

AC will raise the fuel consumption from 15% to 20%. Avoid turning on the AC if it is not really needed.

Do not forget regular maintenance

Even better, change some parts before the recommended time. Change the engine oil every 6,000 miles. Do not wait for the 10,000 miles mark. Do not forget to change the air filter every 15,000 miles. By then, it is already filled with dirt and debris. Worn brake pads will also increase fuel consumption. Change them every 30,000 miles or even sooner if you notice strange symptoms like squeaking when braking.

Check Out What Kind of MPG Can You Get in a DURAMAX?:

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A Duramax’s Average Fuel Consumption

Duramax gas mileage is, on average, around 15 miles per gallon. Depending on the driver, those figures go from 14 to 18. Aggressive and inexperienced drivers will have a higher consumption of fuel. Experienced drivers that know how to work the accelerator pedal will save money on gas and have improved fuel economy. That is how it has been and will always be. You have a say in your car’s fuel consumption.

Ways to Control the Duramax Engine’s Fuel Consumption

There are two main ways to control fuel consumption:

  • Change and adapt your driving style. Avoid aggressive driving and frequent idling. Try to drive at constant speeds as much as possible and slowly accelerate. Plan your trips to save fuel
  • Keep your truck well-maintained. Check which parts can be upgraded to achieve better fuel mileage. Pay attention to regular maintenance. Do regular checkups at the mechanic. Do not wait for a truck to give you a signal for that.

FAQs

Does premium diesel increase MPG?

Yes, it does. Premium diesel fuels increase the overall power output by around 4.5% and add a 5% increase in fuel efficiency. These fuels are enriched with different additives that improve lubrication, power, and fuel efficiency.

Why is my Duramax getting bad fuel mileage?

There are several reasons for poor fuel ratios:

Driving habits. If you often press the gas pedal aggressively, that will take a large sip from the tank. Often driving in traffic jam conditions with lots of idling will also raise fuel consumption
– Irregular maintenance. If you don’t change the filters and fluids on time, that will impact the fuel mileage. Also, the engine and the fuel system need to be completely maintained to get the best fuel efficiency
– Using cheap fuel. Always try to buy high-quality fuel. It will not only save the truck’s components but also save money on fuel in the long run. There is also an option to buy fuel additive and add it yourself.

Does diesel MPG go down in winter?

Yes, a bit. The engine needs some time to warm up, which will cause a rise in average fuel consumption. Also, since sulfur has been taken out of diesel fuels, they have around 3% less energy value when compared to old low-sulfur diesel. All that has a negative toll on the consumption of fuel.

Conclusion

Diesel truck owners have a special type of love for their trucks. Although these engines are louder, more expensive, and have lower fuel efficiency, they offer a unique driving experience. That is why so many drivers will never give up on their trucks.

But, they also know that these engines are not fuel efficient. That is why we all must work together to find ways to save fuel. There are several ways to lower fuel expenses, and the main thing is to change your driving habits. After that, doing custom work on your truck and engine can bring great results. Find parts that will improve fuel efficiency. All these strategies will bring results in the long run.

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Pedro is a skilled automotive expert whose roots trace back to his apprenticeship with the AYES program at PCTI Automotive Technology. There, he distinguished himself by securing state-level accolades in the Ford competition designed for AYES-certified mechanics. In addition to his hands-on technical prowess, Pedro boasts extensive experience in sales, notably within the electrical supply sector.