When it comes to towing, the age-old debate between diesel and gasoline engines reignites with fervor. Whether you’re hauling a boat for a weekend getaway, transporting heavy equipment for your business, or embarking on a cross-country RV adventure, the choice of your truck’s engine can make all the difference. Both diesel and gasoline trucks have their ardent supporters who swear by their respective advantages, but what does the science and performance data say?
In this comprehensive article, we’ll delve into the intricacies of diesel and gasoline engines, examining factors such as torque, fuel efficiency, maintenance costs, and longevity. We’ll also explore how these elements translate into towing capacity and overall performance. By the end, you’ll have a clearer understanding of which engine type best suits your towing needs, allowing you to make an informed decision for your next truck purchase.
So, buckle up and get ready to discover the ins and outs of diesel vs. gas trucks in the context of towing. Your perfect hauling companion awaits!
Diesel vs. Gas at a Glance
Let’s do just a quick overview of diesel vs. gas trucks before getting into the details. We personally have operated both gas and diesel engines for towing. In addition, Tom has extensive experience with maintenance, operation, and even heavy modification and rebuilding of all aspects of diesel and gas engines. We will be sharing our knowledge and experience.
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Knowing the key differences between diesel vs. gas trucks can help you make an informed decision when purchasing a new tow vehicle. It still may come down to just what you can afford, but don’t go into the decision without knowing all of the facts first. Let’s look at eight important side-by-side comparisons of diesel vs. gas trucks.
Power and Torque
Torque is the engine’s twisting capability needed to get mass moving. Diesel engines produce more torque at lower RPMs’s which means higher towing capacities compared to gas engines. This also means that diesel engines will be able to get a load moving and keep it going better. Hills will not slow the vehicle down as much and engine RPM’s will remain lower. Diesel engines also produce their peak torque at much lower RPM’s. This means that getting going and holding speed the engine will not need to to downshift as much.
A diesel truck won’t work as hard to pull an RV up an incline as a gas one. Some RV owners will tell you sometimes it doesn’t even feel like they’re towing anything because the diesel engine has so much power. They can also comfortably travel at higher speeds down the interstate.
This does not mean that gas engines cannot perform these feats; however, it will take a larger engine to match the same capability. Gas engines tend to produce more horsepower which is due to the higher RPM operation. Your gas engine can pull an RV up a hill but will be screaming, which means higher temps, more wear and shorter engine life in these applications.
In the diesel vs. gas truck debate, diesel will always win at the top end of truck tiers. Now that’s not to say that a gas engine cannot do it, In fact, gas engines weigh lots less and that weight can factor into its towing capabilities. To match diesel capabilities however a gas engine needs to get much bigger. In the past Ford even attempted to match its diesel for towing heavy with its 10 cylinder engine. Compare that to a diesel 6 or 8-cylinder that still outperforms it.
There is a reason that every semi truck is a diesel; when it comes to heavyweight operation, they are far superior. We will get into the specific differences that cause these performance improvements in a little bit.
Consider the type of travel you’ll have to make a good decision. And always know the RV’s weight and the truck’s capacity. Never tow anything over the towing capacity of your truck. This reduces the engine life and increases fuel consumption while also putting everyone in danger by ignoring the manufacturer’s warning.
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On average diesel engines are 20% to 35% more efficient than conventional gasoline engines, This is partially because diesel fuel contains 13% more energy than gasoline. When you put similar heavy loads on the engine sometimes the efficiency gain can be 50% or more.
The reason for better fuel economy goes beyond the higher energy density of the fuel. First of all diesel engines operate at higher compression ratios than gasoline engines. This leads to more efficient combustion. Diesel engines often have a longer piston stroke length compared to gasoline engines, which can contribute to more effective power generation and better thermal efficiency as well as torque generation. This thermal efficiency gain means a larger percentage of the fuel’s energy is converted into useful work rather than being lost as waste heat.
Proper truck maintenance improves the overall health and longevity of your vehicle. You may purchase the absolute best diesel or gas truck on the market, but you’ll have problems if you don’t take care of it.
Generally, maintenance on gas trucks costs less. For example, you will pay more for an oil change on a diesel engine because they require more oil. You may also need to change the filters and the separator when getting an oil change on a diesel.
While a diesel will cost more for regular maintenance, maintenance intervals are usually longer for heavy use.
As already mentioned, diesel engines can tow more, at higher speeds, and through various terrain than gas engines. They get better towing efficiency due to the increased torque and power.
That 25 to 35% improvement in fuel economy frequently jumps to 50 to 100% fuel economy improvement when towing. This is due to the lower RPM’s the engine can operate at while towing.
They won’t have as much strain put on the engine or transmission. A diesel-powered truck will pull a 15,000-lb fifth wheel down the interstate just as effectively as pulling it through the Rocky Mountains.
Cost of Fuel
Diesel fuel comes at a higher price than gas on average. Typically it’s anywhere from 20 to 40 cents more in most places around the country. This should factor into your decision, especially if you plan to travel often.
However, many RVers can get a trucker discount card to save on fuel. RVers with diesel engines often get cheaper fuel than those with gas trucks by using fuel programs like TSD Open Roads at the pump. Savings can range from 20 to over 50 cents per gallon.
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Cost of Vehicle
Diesel trucks cost more upfront than gas — usually about $10,000 more. However, they also retain their value longer.
When comparing similar vehicles, a used 2015 diesel truck will cost more than the gas counterpart. So whether you want a new or used truck, expect to pay more for one with a diesel engine.
Reliability and Longevity
Diesel engines tend to last longer than gasoline engines overall. While this is a trend, there are lots of reasons for it. Maintenance is always critical for any engine, and a poorly maintained diesel engine can fail sooner than its gas counterpart. If maintenance is done regularly, however, diesels should last longer for many reasons.
First, as we mentioned before, diesels operate at lower RPM’s. This reduces wear on engine components. Diesel engines also have simpler operating systems. They lack any ignition system, valve timing, throttle plates, and many other components required for gas engines to operate. This simplicity means less to go wrong.
Despite the soot you occasionally see, diesel engines burn more completely and tend to build less carbon residues in the engines. In addition, they operate at lower temperatures, which helps with component fatigue. Diesel fuel itself also has lubricating properties instead of solvent properties, which cause far less wear. Finally, diesels are just built stronger because of their intended use case as industrial work engines. All of these combine into an engine that can last far longer than a gas engine when used for heavy-duty applications.
Personally our diesel truck with 250,000 miles has had no major issues with the engine and we would continue to use it for long trips. We have met many owners with 300-500k miles on their primary diesel tow vehicles.
What Are the Advantages and Disadvantages of Diesel?
The capabilities and longevity weigh in as the biggest advantages of owning a diesel truck. You can do more with a diesel without worrying about how much strain you put on the vehicle. And with diesel engines lasting 200,000 and 300,000 miles sometimes, you don’t have to pay for another truck anytime soon if you take good care of the one you have.
On the other hand, the biggest disadvantage is the cost. You’ll pay more upfront, at the pump, and for maintenance and repair. For this reason, many RVers choose gas trucks over diesel.
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What Are the Advantages and Disadvantages of Gas?
As mentioned above, RVers choose gas over diesel mainly because of the cost. If you only have a budget of $50,000 and don’t want to buy an older diesel truck with over 150,000 miles, then you won’t have many diesel truck options.
It also comes down to the monthly cost of fuel and maintenance. Knowing that one repair bill won’t thwart your budget can bring truck owners peace of mind.
You may also want to consider the payload, especially if you want a truck camper. Because a diesel engine weighs hundreds of pounds more than a gas one, it takes away some of the payload capabilities of the truck. So if you want to carry a lot of weight in the bed, you may prefer a gas option because of its higher payload capacity.
However, gas vehicles have fewer capabilities. Do you want to travel across the country and put hundreds of miles a month on your tow vehicle? If so, a gas truck may not work the best if you tow anything over 15,000 lbs. The strain on the engine could put you in a position to buy a new one in just a couple of years.
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Are Diesel or Gas Trucks Better for Towing?
There is a reason that all semi-trucks on the road are diesel engines (sometimes natural gas but its the same engine). Diesel have better characteristics for heavy loads and are more efficient when pulling.
Towing with a diesel vs. gas truck depends on your needs. If you only tow a 33-ft travel trailer that weighs 10,000 lbs, a gas truck will certainly get the job done. And it will cost less. However, if you tow more than 15,000 lbs and do a lot of traveling, a diesel truck will suit you better.
When shopping for trucks, remember to keep safety as the top priority. You don’t want to endanger the lives of you or other travelers. You also want to protect the vehicle by not putting too much strain on the engine, axles, brake system, transmission, etc. Price and cost are certainly important factors, but don’t push safety to the side.
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What’s the Best Option?
When looking at diesel vs. gas trucks, consider cost, safety, efficiency, power, and longevity.
Additionally, make sure to take care of your truck regardless of whether or not it has a diesel engine or gas engine. Proper maintenance and care after your purchase will make a huge difference in its effectiveness and cost.
So are you in the market for a tow vehicle? Have you weighed all of the pros and cons of diesel vs. gas trucks? What’s the best option for your travel needs? Drop a comment below!
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