7 Things To Know Before Choosing An Isuzu Gas Or Diesel Truck

Adding value to your fleet becomes significantly easier once you read through an Isuzu gas vs. diesel powertrain overview. Isuzu models are known for working hard across a variety of businesses (like cargo or dumpster delivery). That’s why the popular N-Series offers your choice of standard gasoline or diesel powertrains. At Nimnicht Isuzu Trucks, we’ll provide a comprehensive Isuzu truck fuel type comparison so you know what to expect.

Cost of Ownership

This section goes handily to gas. The initial cost of your Isuzu gas truck will be lower than that of a diesel truck of the same class. It’ll also be slightly lower for initial refueling trips and for your first scheduled maintenance.

In addition, for 2026, one of the hidden Isuzu gas truck benefits is Class 3 access. The 2026 Isuzu diesel lineup starts with Class 4, meaning you can’t get a light-duty option if you’re shopping for brand-new commercial-grade trucks.

Fuel Economy and Operating Costs

Isuzu diesel vs. gas efficiency is a significant question, and this category goes to diesel except in very specific situations. Generally, diesel trucks have a major advantage in MPG over their gas equivalent: For example, an Isuzu NPR-HD Diesel model is estimated to reach around 11.98 MPG (Combined).¹ The same NPR-HD with a gas engine is estimated at 9.25 MPG (Combined),¹ which isn’t a significant difference but is a major advantage to the diesel option. In most states, refueling with diesel will be slightly less expensive than the gas equivalent. However, in some very particular regions (like California or Hawaii), regular might save you overall.

Want to see what Isuzu tires will run you, depending on configuration and model? Isuzu gas vs. diesel tire costs can be similar, but this will depend on the tire type, brand, or quality.

Maintenance and Service Requirements

Maintenance costs tend to favor the gas engine. The 6.6-liter eight-cylinder gas powertrain has lower maintenance costs, thanks to more readily accessible parts. But the diesel engine is made to require less frequent service, evening out the expenses. You can see some of the requirements for your yearly service cycle in our Isuzu trucks maintenance guide.

Power, Torque, and Performance

Across our Isuzu N-Series gas vs. diesel comparison, both models utilize similar engines. Here’s a brief overview:

• 6.6-Liter Gas V-8: 350 horsepower, 425 pound-feet of torque, eight-speed auto transmission/Allison 1000 RDS transmission
• 5.2-Liter Turbo Diesel I-4: 215 horsepower, 452 pound-feet of torque, six-speed auto transmission

Usually, gas models have slightly higher payload ratings. For example, the Class 5 NRR can reach 13,611 pounds of payload for gas and 12,970 pounds for diesel.²

Typical Route and Usage

Let’s say you’re focusing on Isuzu NPR gas vs. diesel trucks and want to know why you’d choose one over the other. An NPR gas truck is rated for up to 18,000 pounds of GCWR, making it better suited to light cargo and food delivery (with a configurable bed) and shorter routes.

For 2026, the NPR-HD truck is the lightest diesel configuration. With a GCWR of 20,500 pounds,³ this diesel option can handle machinery, dumpster beds, and more with up to 8,470 pounds of payload capacity.²

Emissions and Compliance

There are significant differences in emissions ratings between these two models, especially with state laws. We recommend our Isuzu engine oil guide to help you keep your driving experience within state compliance doctrines.

Resale Value and Longevity

If diesel engines have one advantage that pushes them over their gas siblings, it’d be their lifespan. Isuzu diesel engines have a B10 durability rating of 375,000 miles, which is perfect for long-distance driving or resale. Gas engines are rated for around 200,000 miles (though they typically go further with proper maintenance).

Isuzu Gas vs. Isuzu Diesel Truck: Pros, Cons, and Recommendations

Once you visit Nimnicht Isuzu Trucks, our representatives will recommend a gas or diesel option, depending on your business and preferences. Generally, a gas truck is best for short-range operations, while a diesel engine is better for heavier loads or cross-country driving.

Frequently Asked Questions

What are the main differences between Isuzu gas and diesel engines?

The primary differences between Isuzu gas and diesel engines are fuel type, costs, and maintenance requirements. Depending on where you live, standard gas may be more accessible and cost less, while requiring less maintenance investment. However, diesels tend to last longer between stops at the station or maintenance bay, thanks to better MPG ratings and fewer service trips. Overall, truckers tend to save on diesel over gas.

Which Isuzu trucks last longer: gas or diesel models?

Generally, diesel Isuzu models are considered to last longer than their gas counterparts. According to the brand, Isuzu diesel trucks have a B10 durability rating of 375,000 miles as of 2017, allowing them to drive for hundreds of thousands of miles while providing consistent performance. Isuzu gas trucks are extremely high-quality but are rated for just over 200,000 miles, making them better for short-range use.

How do fuel costs compare between Isuzu gas and diesel trucks?

The answer to this question depends on your location and your intended use. Fuel costs for gas engines are usually lower, and a gas powertrain is more cost-effective for shorter distances. The cost of diesel fuel is typically higher, but diesel trucks in general are made to be more fuel-efficient, which can be better for high-mileage or heavy-load situations.

Which engine type is better for heavy loads: gas or diesel?

Diesel engines tend to be capable of heavier loads than their gas counterparts. That’s largely due to their higher torque and specific builds, which give them the kick they need to get you into motion. Isuzu trucks are no different; the highest classes use Cummins® diesel engines. Class 4 and 5 Gas trucks can still handle similar weight ranges as their diesel brethren, though.

Featured Reviews For Isuzu Gas Vs. Diesel:

Schedule an appointment at Nimnicht Isuzu Trucks in Jacksonville, FL today!

¹Actual mileage may vary from manufacturer/distributor estimates. Isuzu commercial vehicles are exempt from EPA fuel economy rating requirements, and the fuel economy estimates provided are not based upon such requirements.

²Max payload varies based on accessories and vehicle configuration.

³GCWR ratings assume vehicles are properly equipped with manufacturer-recommended towing setups. Actual weight capacities may vary.