Shopping for a Used Diesel Truck? Here's the Best and the Worst

Dodge W250 (1991½-1993) --This is a Winner, if you can find one.

In April, Autowise.com published their recommendations as regards the best and worst diesel trucks to consider when buying used. These kinds of lists are always fun to review, just to see if the author's views are in alignment with your own.

Personally, I think choosing the best is a more difficult task than identifying the worst. We may have built in biases regarding which features are of greater value to us personally. As we've written about before, it depends a lot on what you're using your truck for.

On the other hand, picking the worst is much easier. Why? Because the bad trucks, like those selected by Riley, the author of this piece, have a reputation. We're not talking about "Friday trucks" or "Monday trucks" where assembly workers are distracted or foggy. We're talking about bad engineering. 

The one positive about some problems is that it gives aftermarket engineers an opportunity to create fixes for some of these mistakes. Not all design flaws are that easy to resolve however. Which leads to our story.

The title of the piece is 8 Best Diesel Trucks You Can Buy & 4 of the Worst. 

The article begins with the basic reasons why people buy diesel trucks. First, they're workhorses. If you're towing a boat, ATVs, a camper trailer or hauling bricks, you know the importance of having equipment that's up for the task. 

Riley's concise description of the benefits of diesel is worth memorizing. Diesel engines "get better fuel economy, are often easy to modify with aftermarket parts, and, when properly maintained, will basically run forever. This makes them a great deal if you are looking for a used truck." 

All this is a plus for diesels, but there's a minus, too. A well maintained, low-mileage vehicle can cost a pretty penny. That's OK with some of the best trucks, and totally not OK if you select a clunker.

That is why this article was written, to help us avoid purchasing a truck that has little more value than a lawn ornament. 

The Autowise article begins with the 8 champion selections, then flashes warning signs regarding the losers. I will discuss the worst first, and list the 8 trucks they have labelled "the best." 

THE WORST

Here are the four diesel trucks that this article recommends you avoid. Sadly, these  trucks that have helped give diesel a bad name in some circles. 

Chevy & GMC C/K 5.7L (1978-1981)

Older folk are familiar with the Oldsmobile debacle in which GM dropped a 5.7L diesel engine into an Olds. It went down in history as one very bad decision. Ironically, GM took this same engine and decided maybe it would work in a pickup. Two wrongs don't make a right. One problem was that this particular engine was a gas 5.7L converted into a diesel. There were other problems as well, Riley writes. Ultimately, the only thing going for this truck is the vintage look. Buyer beware.

Chevy & GMC C/K 6.2L (1982-1993)

GM learned some lessons by this point in time and decided to exit the diesel engine building business. They turned to a neighbor, Detroit Diesel, to undertake this task. Unfortunately, what they delivered was a 6.2L engine that looked like it should have power because of its size. Such was not the case. The 130 horsepower it delivered is only 40 hp more than today's Smart Car. The other problem this engine had was a tendency to leak oil from the rear main seal. Not good. To fix this issue required removing the tranny, and you can be sure that was neither easy nor cheap.

Chevy & GMC C/K 6.5L (1994-2001)

You'd think by '94 GM would have this diesel business figured out, but no. The turbocharged Detroit-built 6.5L had a new set of problems. It was also behind the curve with regards to its indirect injection and couldn't compete with the Cummins and Powerstroke engines of the same time period, engines with 50% more power. Add to this the mechanical issues and your best best is to avoid them altogether. Riley says, "Get a Duramax."

Ford Super Duty 6.0L Turbo(2003-2007)

The article tags this engine as "by far the worst modern diesel engine." The engine was so bad that there were legal battles between Ford and Navistar (the parent company of the Powerstroke.) The list of problems this engine had includes head gasket issues and catastrophic fuel system failures. To make matter worse, to do some of these repairs required removing the cab in order to access the parts. Yikes. Riley recommends avoiding this one as well and find a 7.3L Powerstroke. You will be much happier.

THE 8 BEST DIESEL TRUCKS YOU CAN BUY 

If you're brand loyal, there's something for everyone here. You can read about each of these at Autowise. If you have different opinions here, feel free to leave a comment. 

Chevy/GMC 2500 & 3500 (2006-2007)

Dodge Ram HD (2003-2004)

Ford F-250/F-350 (2008-2010)

Dodge Ram 1500 (2014)

Chevy Silverado HD (2012)

Dodge W250 (1991½-1993)

Ford Super Duty (1999½-2000)

Dodge Ram 2500HD (2010)

Source: https://autowise.com/best-diesel-truck/

The Legendary First-Generation Cummins 6BT Diesel Engine

You can tell who the diesel guys are by the way the write about diesel engines and diesel power. From the getgo, there's a sense in which we're always having to be a little defensive, write in a more calculated manner. 

So it is that Henry Cesari's article Monday at Hot Cars begins with this observation: "Diesel engines are divisive: there are many unfair myths surrounding diesel engines." It's almost as if he's saying, "Let's get this out of the way. If you don't like it when I write about diesels, go read something else." We like it and yes, we know diesels have pros and cons, but they're not going to be extinct any time soon. Their role is currently too important.

This article is about when Dodge trucks were mated with Cummins engines to produce the popular, much-heralded 1989 Dodge Ram. It's titled, Looking Back At The First Generation Cummins-Powered Dodge Ram Truck.

It's a great story. From initial vision to completion it took more than five years. When I think about how impatient everyone is today it's obvious that it takes real resolve to complete truly great projects. In most cases--the exception being the Harrier jet--the bigger the plane, the longer the runway required to get it off the ground. Kudos to Dodge and Cummins for their determination and commitment.

Dodge was famous for its trucks long before the Cummins-powered Dodge Ram. The Power Wagon and the Li'l Red Express, for example, were exceedingly popular. Today, 75% of Dodge Ram 2500 and 3500 buyers opt for the Cummins engine option, which is able to tow nearly 15 tons with ease.

Cesari not only did his homework, he produces a stimulating read, writing "when thirty years ago, Dodge shoe-horned a Cummins-built diesel engine--intended for heavy equipment use--into their Ram pickups, the two companies incited a diesel revolution. Today, we're looking back at the Cummins-powered 1989-93 Dodge Rams." 

It's surprising how much was involved with making it work. In addition to an impressive engine makeover they followed up with 11 million miles of testing to ensure they'd actually produced a a power plant that was strong but that would also last.

According to Cesari, the Cummins team overbuilt every aspect of the new 6BT engine. The engineers incorporated "seven main bearings on the crankshaft, and six head bolts for every single cylinder. The company built both the block and head out of cast iron. They spared no expense in forging, hardening, and testing components such as the crankshaft, the connecting rods, and the pistons. When Cummins purchased components from outside vendors, they opted for the highest possible quality: the injector pump and the injectors are all durable Bosche units." 

The Cummins-powered 1989-93 Dodge Rams were pretty special. They set the bar high for everything that would follow. The Dodge team knew there could be no shortcuts. Their reputation was on the line.

Read the full article HERE at HotCars..com

For another fun Cummins/Dodge related read this one by Michael Van Runkle also, about a slammed 2019 SEMA special that features a 5.9-liter Cummins turbodiesel engine, stacks, and drop dead good looks.