Truck Wars: Who Has the Most Powerful Heavy Duty Diesel

Last week, TheFastLaneTruck.com published an article by Andre Smirnov comparing the latest and greatest details of our 2021 heavy-duty diesel truck offerings from the Ford, Chevy and Ram families. It includes a video, billing itself as Heavy-Duty Diesel Truck Wars! 

Smirnov takes the approach of a conscientious private detective, patiently assembling data and making useful comparisons. When all is said and done, will it be the 2021 Ford Super Duty, 2021 Chevy Silverado HD / GMC Sierra HD, or the 2021 Ram HD?

The starting point for his analysis is a straight up comparison of power output and torque. The highest horsepower was generated by the Ford Super Duty, its 6.7L V8 turbo-diesel cranking 475 hp. The torque monster, however, turns out to be the 2021 Ram HD, edging the Ford with 1,075 lb.-ft. of torque. Here are the numbers:

	2021 Chevy/GMC HD	2021 Ford SD	2021 Ram HD
Engine	6.6L V8 turbo-diesel	6.7L V8 turbo-diesel	6.7L I6 turbo-diesel H.O
–Power	445 hp	475 hp @ 2,600	420 hp
–Torque	910 lb-ft	1,050 lb-ft @ 1,600	1,075 lb-ft
Transmission	10-speed auto (Allison brand)	10-speed (Ford)	6-speed (Aisin)

It's interesting to see the places where these power plants differ. Note the slightly smaller Chevy/GMC engine. It's also interesting how the Ram has a 6-speed transmission whereas the competitors utilize a 10-speed setup.

When it comes to towing and payload ratings, Smirnov notes that this is where the manufacturers are digging down, fighting for your dollars. That's because at the end of the day you want a work truck that can work.

The first comparison is of the maximum tow ratings for diesel-powered one-ton dually trucks with a regular two-door cab, rear wheel drive only. A follow up chart provides max payload ratings for gasoline-powered two-door 2WD trucks. The conclusions he draws are surprising:

While the diesel-powered trucks have the torque and power to tow great big trailers and the exhaust brake systems to slow them down, the diesel engine itself adds weight to the truck. As such, if you want maximum payload from your heavy-duty truck, you need to choose one that is powered by a lighter gas engine.

This is first place where Smirnov dons a Sherlock Holmes twist, comparing not just the trucks but the method of trailering, either gooseneck or 5th-wheel. 

Then like a sidewinder he throws another curveball, suggesting that many people prefer crew cabs and 4WD so they can carry more people. And what about a 2021 dually crew can with that 4x4 configuration? Shouldn't we compare these, too?

After laying out the numbers for these he continues still further to the 3/4 ton diesels, and by the time he gets to the end what have we learned? That the verdict is still out, sort of. The author states that they will be updating data as additional information comes in.

The article ends with a video designed to make us hungry for more diesel action in person than what we could share in 2020. HERE is the link for Truck Wars.

Thin Is In: Heavy Duty Oils Getting Lighter

It seems like forever that 15W-40 oils were "the choice" for heavy duty diesel engines. Or at least for centuries. No, I s'pose that would be decades. 

All this has been changing though, and in ways we couldn't imagine at one time. 

I do remember when I first noticed passenger car oils getting thinner. When I saw the first 0W-30 I thought it interesting. Even more interesting, though, was when I looked at the Society of Automotive Engineers (SAE) registry for upcoming oils, there were actually 16 companies with a 0W oil registered, even though they were not yet in production. 

I later saw an article in Lubes N Greases (LNG) about SAE 0W-16 and 0W-12 and 0W-8 oils that were coming and more recently the 0W-0 oils being tried in Japan. 

This week, George Gill wrote an LNG feature on thinning oil viscosities in the diesel market. The story is titled Heavy-duty Shifts to Lighter Oils. In recent years, 15W-40 diesel oils began yielding market share to lower viscosity SAE 10W-30 oils. 

Part of the reason is the fuel economy benefit that lighter oils offer. For over-the-road truckers, the cost of fuel alone is 30 to 40% of a trucking firm's overall costs. (I bet you didn't know that.) Another reason, according to the article, has to do with the new engine architecture with its tighter clearances, thus requiring thinner lubes that can flow more readily to engine components.

There's a third reason for the thinner oils. In colder temps these lower viscosity oils will decrease warm up times and provide better protection in colder climates.

You may be wondering, though, "Is my engine still protected?" The answer to that is that this has been going on for years now with millions of miles of data to support this move to lighter oils. 

CK-4 and FA-4 
The article turns to address the newer API categories of CK-4 and FA-4. CK-4 was designed to have backward compatibility built into it. This has resulted in wider acceptance of the new designation. FA-4 oils are not so versatile. FA-4 oils in modern contemporary engines, however, do offer a 1% fuel economy improvement, the article states.

Despite the benefits outlined for thinner oils, 15W-40 remains the category leader for heavy duty diesel engines, but 10W-30 is the fastest growing segment during these past 10 years.

READ THE FULL STORY HERE:
https://www.lubesngreases.com/lubereport-americas/heavy-duty-shifts-to-lighter-oils/

RELATED LINK
CK-4, FA-4? Still Confused About Diesel Engine Oil Specs? 

Photo by Matthew T Rader on Unsplash