With today’s increased fuel prices, many truck owners and RVers are looking into towing capacity and fuel consumption. Although modern engine technologies offer better mileage and reduced emissions, everyone wants to stretch the mile to the gallon as much as possible. Isuzu’s D-Max is very popular among business owners and towers due to its exceptional off-road reliability and fuel efficiency.
However, does it still maintain its renowned fuel economy when towing? When towing a caravan of 2200kg along a mix of country roads and freeways, the Isuzu D-Max has a fuel consumption estimate of 14.5 to 16 liters per 100km. However, in reality, fuel consumption when towing varies a lot.
This article will help you understand factors that affect fuel economy when towing and how you can make it more efficient.
How towing affects your Isuzu D-Max fuel consumption
The average fuel consumption of an unhitched Isuzu D-Max is 8 liters per 100km, depending on model year and body style. Additionally, you may experience an average of 5 to 10 mpg decrease in fuel mileage when towing.
However, other factors besides weight significantly influence fuel economy when towing, such as fuel type, driving speed, terrain, drag, and driver.
Generally, gas mileage decreases when towing even for diesel engines such as the one in an Isuzu D-Max and Isuzu MUX. This means the heavier the load, the more force you require to tow it. Therefore, the more force the engine puts out, the more fuel it will consume.
Estimates claim that every 100 lbs. of extra weight in a truck reduces fuel economy by 2%. Therefore, towing a larger trailer will create a larger drop in fuel economy.
Additionally, there’s a drag to consider. Drag is the effect of wind resistance a truck and trailer have, therefore forcing the engine to work even harder and eventually lowering the fuel economy.
How to get better fuel economy when towing
Although towing increases your vehicle’s fuel consumption, you can still improve its mileage. Even though the Isuzu D-Max is a fuel-efficient vehicle, a 5-mpg increase in fuel economy is a huge save. We will give several tips on how to get the most miles for your money when towing with the Isuzu D-Max.
Reduce your driving speed
You need to close attention to your speed when towing. For instance, driving downhill will increase your mileage, but slow driving and early braking will also improve fuel economy. In addition, it helps keep a consistent pace, meaning fewer stops. If you can, avoid high-traffic roads to increase miles per gallon. Then use cruise control when you get to flat road.
Driving at higher speeds while towing increases fuel consumption because it takes more fuel to overcome drag (wind resistance). Slowing down to 10 mph will likely increase your vehicle’s MPG by 6 to 8 mpg.
Reduce your weight
Increasing your vehicle’s overall weight will force the engine to work harder. The harder your engine works, the more fuel it consumes. Therefore, you will have to minimize the weight of your vehicle and trailer to improve its MPG. Reducing weight also reduces resistance and helps improve mileage.
An increase in 200kgs can increase the fuel consumption by about 2 to 5 liters per 100 km. Therefore, understanding your vehicle’s towing capacity and the payload is important to avoid overloading.
Consider how you load
Sometimes, you may not control your haul’s weight, but you can control how you pack it. Note the load distribution on your wheels is correct so that your tow vehicle can do its job efficiently.
You can improve your vehicle’s aerodynamics by removing things that stick out of the roof. Also, try lowering every piece of equipment you have, keeping them compact and level. This means the less wind resistance there is, the more efficient your vehicle will be.
If your trailer is taller than your tower, it can create pockets of wind resistance. Go for a shorter one or install a wind deflector on your car to help avoid this. Wind deflectors can reduce fuel consumption when towing by 2 to 3 liters per 100kms.
Too much weight at the back of the trailer will lift the front wheels, increase the drag on the rear wheels and eventually increase fuel use.
Avoid driving in windy weather
Towing during a windy day will increase fuel consumption, especially if driving against wind direction because it increases aerodynamic drag. On the other hand, if you’re driving with the wind, your velocity through the air is less than the vehicle’s speed.
Although you can’t always predict weather or change postpone drives, try waiting out strong winds if the opportunity presents itself.
Increase your tire pressures
All vehicles and trailers have recommended tire pressures for various weights. Maintaining these tire pressures will affect not only your drivability but also your fuel economy. Research states that drivers experience a 0.2% decrease in gas mileage for every 1-psi drop in tire pressure. That may not seem significant, but it can result in proper savings over time.
Inspect your tire pressure before towing to ensure they are at proper levels. We also recommend packing a tire pressure gauge and a portable air compressor to help top up your tires if they are low.
Also, many drivers believe that pumping an additional 5 and 10 PSI in your tires will reduce fuel consumption. However, don’t go overboard, as it can reduce the contact patch of the tires with the road, reducing traction and handling. It can also be dangerous.
Keep up with your vehicle maintenance
Another thing that gives good gas mileage when towing is proper vehicle maintenance. Skipping service on your towing vehicle and vehicle can limit your fuel efficiency significantly. Ensure your mechanic checks all the vehicle systems are in proper working conditions, such as fuel injectors, transmission components, and Mass Air Flow Sensor, to improve fuel mileage.
- Change your oil regularly and use your manufacturer’s recommended oil grade.
- Have your mechanic check and replace your air filter. A dirty air filter will limit air flow to your engine and affect the energy production necessary for towing.
- Use manufacturer-recommended diesel additive to clean the fuel and improve engine performance, hence better fuel mileage.
- Ensure to lubricate all moving parts and fix any large dents which could affect wind resistance.
Avoid idling
Your fuel economy when idling is zero miles per hour. Although most modern engines shut off when it detects you’ve stopped temporarily. Suppose you’re towing and planning to sit idle; it’s best to shut off your engine so that you can only use your fuel for driving. Idling not only wastes gas but also contributes to pollution.
Conclusion
Because of all the factors involved, it’s hard to say with certainty how much fuel the Isuzu D-Max consumes when towing. But your fuel consumption when towing will always be higher, thus reducing fuel mileage. Still, following these steps to improve your fuel economy will help you make the most of these limitations and help you save some coins.