Diesel has come a long way in the last few decades, and there are few ways to better illustrate that than by looking at modern Ford diesel trucks. From the F-150 to the F-450, every Ford full-size truck now offers a diesel option. Far from the sooty cacophony of old, these sleek machines take diesel and make torque rather than smoke. Ford diesel trucks have taken advantage of the strengths of the diesel engine for decades now and have developed the technology to the point where many of the commonly associated pitfalls of diesel no longer apply.
Diesel engines primarily differ from gasoline engines in that they don’t use spark plugs. Instead, they simply compress the air and fuel mixture to the point where it spontaneously combusts. The advantage of this is very high thermal efficiency, far more than any other type of internal combustion engine. These engines are ideal for low RPM applications requiring high torque. Essentially, they are a perfect match for use in trucks, especially the heavier duty work trucks and those pulling heavy loads.
For the F-150, diesel engines are about offering peace of mind for the average motorist who needs to tow things regularly while still maintaining excellent fuel efficiency. Whether the object being towed is a trailer loaded with gear, a boat, a small camper, or any other standard load, the 3.0-liter Power Stroke turbo-diesel option will get you to your destination without drama.
Meanwhile, the 6.7-liter Power Stroke turbo-diesel powering the F-Series Super Duty models is the next step up in power. The F-250, F-350, and F-450 are all meant for heavier duty use than the standard F-150 and thus require considerable torque to achieve the same levels of performance that the F-150 does in its class. When it comes to any diesel Super Duty, overkill is the name of the game. There are very few loads a Super Duty will have trouble with, and those tend to include things that semi-trucks are normally used for. To give some hard numbers, the 2021 F-450 Super Duty is rated to tow an incredible 37,000 pounds with its standard Power Stroke diesel engine.
Ford’s Current Diesel Engines
The two diesel engines available in current F-Series trucks are both turbo-diesels designs that enhance the engines’ capabilities through turbocharging. Both engines are sized to provide the best torque and efficiency possible for the platform, taking into consideration what that platform is normally used for and the structural makeup of said platform.
For the standard F-150, the diesel option is the optimized 3.0-liter Power Stroke V6. This is a turbocharged and intercooled 60-degree V6 diesel engine composed of a compacted graphite iron block with aluminum heads. The compacted graphite iron block is essential for having a long-lasting turbo-diesel engine, as it is an extremely dense and sturdy material that can handily keep the diesel engine’s tremendous pressure contained for years on end without issue. The aluminum heads mean the engine’s fast-moving mechanical parts are kept as lightweight as possible, minimizing their wear and therefore maximizing their life.
The engine displaces exactly 3 liters, with a compression ratio of 16 to 1. The compression ratio of an engine describes how much the air inside is compressed during its operation, and a higher compression ratio is a good indicator of engine efficiency and power. Most well-tuned modern turbocharged gasoline engines have compression ratios around 10 to 1. A compression ratio of 16 to 1 is unique to diesel engines and is indicative of how hard they compress the air forced into them by their turbochargers – it is compressed hard enough to spontaneously combust, after all.
All this compression and combustion leads to 440 pound-feet of torque at an incredibly low 1,750 RPM. With this kind of torque and the engine’s smooth engagement, you will have no trouble taking off from a start with a trailer in tow or climbing hills at low speeds. In fact, you could genuinely forget that you’re towing some small loads.
On the other end of the spectrum is the 6.7-liter Power Stroke V8 turbo-diesel. It is a 90-degree diesel V8 with a single turbocharger, run with in-block cams and overhead valves. Similar to its smaller cousin, this large displacement V8 is built with a compacted graphite iron block and aluminum heads. However, its compression ratio is 15.8 to 1, which may seem curious to some. This is, after all, a far higher performance engine than the already powerful 3.0 diesel, so why does it not compress air as hard? Well, that’s because the 6.7-liter is designed for reliability as well as power.
In fact, earlier versions of the 6.7-liter Power Stroke did have a higher 16.2 to 1 compression ratio. However, in 2020, Ford upgraded the engine for enhanced reliability. One of the major changes was adding new steel pistons and a forged crankshaft, and the sturdier design reduced the compression ratio slightly to 15.8 to 1. But thanks to other tweaks, such as an upgraded turbocharger and higher-pressure fuel injectors, overall power increased to an earth-shattering 1,050 pound-feet of torque at a frankly shocking 1,600 RPM. Definitely overkill, but in a very useful way.
What Can a Diesel Do?
What all that power does when the rubber meets the road is what makes that dramatic overkill so useful. In the case of the F-150, the diesel engine elevates the SuperCab variant’s Gross Vehicle Weight Rating to just over seven thousand pounds while bringing the payload up to 1,840 lbs. The heavier Supercrew configuration manages a 1,805 lbs maximum payload when diesel-equipped while being able to tow a whopping 12,100 lbs with the Max Trailer Tow Package installed. It should be noted that the diesel F-150 comes with an extended five-year or 100,000-mile powertrain warranty – those compacted graphite iron blocks can take a beating.
Meanwhile, the Super Duty is capable of even larger numbers. The F-250 diesel can tow no less than 22,800 lbs – nearly twice what the F-150 diesel can handle. The F-350 diesel goes beyond that with a 35,750 lbs max tow rating, thanks to its stiffer suspension and dual rear wheel configuration. The numbers just keep getting larger as one moves up the food chain, and the top of the line F-450 (which is only available as a diesel) is rated for an incredible 37,000 lbs of towing capacity.
Take Your Truck to the Next Level With a Diesel Engine
Modern diesel engines are not just clean-burning but monstrously torquey. They have the power and efficiency to take on and complete just about any task when dropped in a modern Ford pickup truck. Diesel trucks like the F-150 with its 3.0-liter Power Stroke are more than enough to handle the vast majority of missions. With the agility and ease of use that larger trucks just don’t have, the F-150 is the perfect weapon for the weekend warrior. Meanwhile, for those who require a full-time capability for the toughest tasks, look no further than the F-Series Super Duty trucks armed with their 6.7 Liter Power Stroke diesel. No matter your needs, there is a Ford diesel truck for you.