QUEST FOR THE HOLY GRAIL
I own a 2016 Ford F-250 Crew Cab Diesel 4x4. I am currently averaging a disappointing 14 mpg while running completely stock. I am weakening to the ads for products that promise a fuel economy increase. Would you help me locate the best products for improving fuel economy?
Lonnie Dotson Watsonville, CA
Many of the aftermarket products available today that are advertised as “fuel economy”
upgrades can provide a small bump in fuel economy. Generally, the biggest payback for an aftermarket product or modification usually involves a power increase or an improvement in either the appearance or function of the truck. If you’re concerned at all about losing your powertrain warranty, stay away from products that increase the fuel rate, change the injection timing, affect emissions, or increase boost pressure—that is, computer programming.
The new diesels are tuned to work with the factory-installed air intake and exhaust systems. Aftermarket manufacturers are beginning to offer products that don’t affect emissions and/ or the new truck warranties, so you’ll have to ask before bolting it on—if you’re worried about your truck’s warranty.
It’s been our experience that a modest power increase can improve towing fuel economy by up to 10%. We mostly attribute this to the fact that the truck can remain in overdrive more of the time. A 10% improvement in fuel economy equals a savings of about 25-30 cents a gallon, depending on the cost at the pump. For those who put fuel economy at the top of the list in importance, we recommend doing the easy and cheap things first. 1). Track every gallon of fuel that goes into your truck’s fuel tank. Tracking fuel economy over several thousand miles and throughout the year will give you valuable information that can be used to identify trends or evaluate products. Many truck owners only have a general idea what their truck’s fuel economy really is. 2). Do the easy and less expensive mods first. Run your front tires at their maximum rated pressure as listed on the sidewall. Adjust the air pressure in the rear tires to match the tire squat produced by the front (an empty truck will have a weight bias toward the front). This usually results in 10-20 psi less air pressure in the rear tires when running unloaded, and an air pressure nearly equal to the front when loaded. Rolling resistance is a big factor in fuel economy. Soft tires rob fuel economy. 3). Slow down and drive near your engine’s specified torque peak rpm. The 1,800-2,000 rpm range usually works well for diesel pickups, and will be the sweet spot for fuel economy. In the “frame of mind” category, drive like the “low fuel” warning lamp is lit and you still have another 50 miles of interstate to drive before the next fuel stop. We’ve only seen the low fuel warning light once or twich in our own trucks, and it completely changed how we drove that last 50 miles. Through the years Diesel World has been genuinely engaged in the area of diesel fuel economy improvements. A subscription could be worth its