All my opinions:
Rarely does a diesel make more sense than a gas engine, in 2021. The diesel is only the better option when the following applies:
-Towing around 20k, or more, often.
-You run almost exclusively highway miles with nearly zero trips being less than ten miles.
-The vehicle will be driven at extremely high altitudes, nearly all of the time.
or
-You want a diesel and can afford the mishaps and downtime.
My tow rig is a 2014 F-350 crew cab, chassis cab, dually with a 6.2L gas engine spinning a 4.30 rear axle. I can legally put over 5k on my ten foot flatbed. I regularly tow my 16’ dump trailer at around 15K. It’s very well mated. Now, where I live, there isn’t more than a few feet of flat land, anywhere. However, I don’t live in mountains, not even close. On the other hand, wind here is usually around 20 MPH and frequently over 30 MPH. My load typically is not a big wind sail, but sometimes, when I haul equipment, it is. If I was pulling a large travel trailer, I may have different experiences. There are a lot of people using this engine with them, all over the country, who don’t have issues, so I don’t think I would, either.
Lets go through my list.
For gas engines...Well equipped half tons have been rated at 10k, or over, for many years. A ”3/4 ton” is very well suited to fit in the “I’m towing 10k-15k” column. A single rear wheel “one ton” is pretty much a 3/4 ton, plus a little bit beefier suspension. The SRW one ton is just slightly more capable, often adding less than a ton of towing capacity. When you move to a dually (DRW), you get a lot more suspension capability. Often, another ton, or two of towing capacity and over a ton of payload. If you really want payload capability, get a chassis cab.
The only reason they put diesel engines in 3/4 tons is because they sell. From a functional standpoint, they make no sense. Almost no 3/4 ton can handle the payload (by ratings) needed to tow what they are rated at. The only way most of them could tow at max, without going over their ratings, is if they have a gooseneck trailer with the entire payload of the trailer directly over the trailer axles. Ironically, diesel engines weigh more than gas engines, so it gets penalized even more over its rated payload, before you put the trailer on.
The modern diesels really need to be run. Many miles with constant RPM‘s are needed, not optional. The more miles you can put on, each time you shift from Park, the longer the engine will last and the more likely it will be trouble-free. Short trips or trips where the emission system can’t get and stay in its optimal range will generally provide a litany of problems.
At high altitudes, the forced induction of the turbo will really shine. This is the one area that makes the decision more difficult. Gas engines just can’t make the power, way up. This doesn’t mean, “I need a diesel, I drive through the mountains, once a year”. If you live in high altitude, I’m referring to you.
Even with the best preventative maintenance, very few modern diesels live as trouble-free, mile for mile, as the current crop of HD gas engines. Again, if you’re towing 25k and driving more than 20k miles, per year, I’m not talking to you. That is what the diesel is for.
Let‘s look at the currently available gas engines.
Ram has the 6.4L. This engine, in its current firm, is fairly new. It is very capable, but has cylinder deactivation. From what I have seen, no engine with cylinder deactivation will last nearly as long as the same engine without it. Our shop has a Ram 5500 with this engine. So far, so good.
Ford has the 6.2L that is old school, very capable. It’s been out since 2011 and in 2017, got a slight modification. The torque is more and peaks at a lower RPM than the 2011-2016 models. I have had my 2014 over three years. Most of its life has been towing or hauling. They have recently introduced a 7.3L that thus far has gotten rave reviews.
GM has the recently released 6.6L. It replaced the 6.0L that was a fantastic engine that lasted forever, it just didn’t have the power to compete with the Ram 6.4L or Ford 6.2L. Not even close. The 6.6L is proving to be a great engine, too. Our shop got a couple, in crew cab pickups. It is a world above the old 6.0L it replaced.
With any of the gas engines, it’s best to get the highest numerical value rear axle available. Fuel mileage will be slightly hurt, but towing capacity will be greatly increased.
