When it comes to the American diesel truck market, the three big names are Duramax, Powerstroke and Cummins. These engines are found in General Motors, Ford and Dodge trucks respectively. All three engines have plenty of loyal fans as do the truck brands themselves.
Is one better than the other? All three have pros and cons. Cummins diesel engines are largely considered to be the powerhouse when it comes to towing, but what about Duramax and Powerstroke engines? Let’s take a closer look at the Duramax vs Powerstroke trucks.
Although the first GMC diesel engine began selling in 1982 and Ford started selling a diesel engine shortly thereafter, the Powerstroke and Duramax names weren’t used until later with Powerstroke beginning in 1994.5 and Duramax beginning in 2001.
The first Ford diesel was the 6.9-liter IDI. It was made by International Harvester and it featured direct injection. But the first Ford engine to feature the Powerstroke name was the 7.3-liter in 1994.5. This engine went on to be an industry leader for almost a decade.
The subsequent Ford diesel engines were designed with stricter emissions guidelines in mind. Initially, that didn’t go smoothly. The 6.0-liter Powerstroke had more power than the 7.3-liter, but it also had a long list of problems that included clogged EGR valves and head gasket failure among other problems. Fortunately, the later generations of Ford diesels improved by quite a bit.
The current 6.7-liter Powerstroke turbodiesel has the following features:
The first Duramax diesel was the 6.6-liter LB7 built in 2001. The LB7 was replaced with the next generation LLY in 2004 which was also considered a reliable engine. The LLY was replaced with the LBZ in 2006 and it featured upgraded power and efficiency. The LMM engine was released in mid-2007 followed by the LML in 2011. This latter engine was the first Duramax able to use B20 diesel which is a mix of 80% standard diesel and 20% biodiesel.
The latest GM diesel is the 6.6-liter Duramax L5P which debuted in 2017. This engine has the following features:
One of the biggest reasons people choose diesel trucks over gas trucks is towing capacity. Towing requires significant torque and diesel engines make a lot more torque than gas engines. So, does GM or Ford make more torque? As you might expect, it depends on the engine. A Ford Super Duty with a 6.7-liter Ford diesel makes 935 pound-feet of torque. A comparable truck is the Chevy Silverado HD with the 6.6-liter L5P GM diesel which makes 910 pound-feet of torque. Take a look at the torque ratings for Powerstroke engines over the years:
The earliest GM diesel put in Chevy trucks was a 5.7-liter and it made 220 pound-feet of torque. The next engine was a 6.2-liter diesel made in a collaboration between GM and Detroit Diesel. It made 240 pound-feet of torque. GM then partnered with Isuzu to make the Duramax.
Both the Ford and GM diesel engines have stayed relatively close in how much torque they produce. The current engines are only 25 pound-feet apart.
Although horsepower isn’t as important as torque for towing, it’s still important. Horsepower allows you to accelerate faster whether you’re towing or not. In this category, the latest generation of Ford and GM diesel engines are very close in performance. The Ford engine makes 450hp and the GM makes 445hp.
Looking back at previous Ford and GM diesel engines, the numbers were still very close. For example, the first Powerstroke finished with 275 horsepower when it ended production in 2004. Around the same time period, the GM LB7 engine debuted with 300 horsepower. The next Ford engine was the 6.0-liter, and it had just a bit more horsepower than the LB7 at 325hp. However, the next generation of GM diesel finished with 360 horsepower.
Verdict: both the Ford and GM engines have been – and will likely continue to be – very close in horsepower numbers.
Towing capacity is determined by a few factors which include torque and horsepower. It also depends on the truck. For example, 2WD trims can tow more than 4WD trims. The current towing capacity for diesel GMC and Chevy trucks maxes out at 23,300. Ford trucks with the latest Powerstroke engine can tow up to 34,000 pounds. For most drivers, the 23,300 number is plenty for towing most types of boats, campers and horse trailers. It’s also worth noting that, in the United States, a commercial driver’s license is required to tow more than 26,000 pounds.
Diesel trucks are ultimately meant to be work trucks, so great fuel economy isn’t usually a priority for these heavy-duty trucks. However, diesel engines are more efficient than gas engines, so most diesel engines do get better fuel economy than their gas counterparts. Take a look at some fuel economy figures from trucks with both the Ford and GM diesel powerplants:
It’s worth noting that the EPA doesn’t require fuel economy numbers for vehicles over 8,500 pounds. The numbers for the heavy-duty trucks listed above were gained through real-world tests and not EPA estimates.
GM diesel engines are known to last up to 500,000 miles when properly maintained. However, the key to longevity is keeping the truck together around the engine. With that in mind, the reliability ratings of GM trucks tend to be lower on average than Ford trucks. The Ford diesel engine is also known to last between 300,000 and 500,000 miles.
The diesel engines in both light-duty and heavy-duty GM trucks are covered with a five-year or 100,000-mile warranty. The Ford Class 6 and 7 medium-duty trucks with a Powerstroke engine come with a 250,000-mile warranty. Otherwise, the warranty on the Powerstroke is five years or 100,000 miles just like GM.
In terms of popularity, it’s hard to deny that the Ford pickups come out ahead. Ford pickups are not only the most popular truck brand in America, but the popular F-Series trucks have been the best-selling vehicles in America for many years.
Buyers looking for the best diesel fuel economy would be hard-pressed to find anything more efficient than the 2020 Chevy Silverado 1500 with a Duramax diesel. Buyers looking for the highest towing power and overall reliability between the two brands are more likely to look at the Ford diesel pickups.
Whether you decide to get a Ford diesel or a GM diesel, rely on ProSource Diesel for all your diesel truck parts needs. ProSource is where repair shops shop for Chevy, Dodge or Ford diesel truck parts.