I considered doing this post before the posts on specs, but it is too easy to be biased towards an engine rather than the necessary specs.  Thus I decided to hold off and reverse the order in the hopes I could help you make an unbiased choice.

So, you’ve settled on how much luxury you need, how much you plan to tow or load the truck with, and possibly figured out a range of specs you want to focus on.  The basic manufacturers of trucks designed for actual work are Toyota (Tundra), Chevrolet (Silverado series), Dodge (Ram series), and Ford (F series).  Each of these offers their trucks in gas engines and diesel engines, except the Tundra, which only comes in a gas engine at this time.  True work trucks, often labeled “HD” for Heavy-Duty,  are usually purchased due to their cheaper price tag and “get the job done” design.  The true workman of the trucks would have a diesel engine, however, this increases price by about $8,000 on average, so many buyers stick with gas if they don’t absolutely need the power.

The first thing you need to ask yourself is, “What EXACTLY do I need my truck to do?”  While anyone with money to burn can go out and spend $45,000 (or more) on a great, oversized, fancy work truck with a diesel engine that will pull or haul almost any typical farm or ranch load, I am assuming that if you are researching trucks, you are more likely trying to find just what you need and not desiring to spend any extra.  While deciding on the best engine doesn’t require quite the research as all the specs discussed previously, there are a few things you should be familiar with.

Gas engines have been around a while, and come with automatic and manual transmissions.  Gas engines have plenty of power for most standard jobs, and on average, we found gas engines could tow up to about 12,000 lbs pretty comfortably.  Gas is an easy fuel to come by, and these days it is much cheaper than diesel.  Gas engines are also much less expensive to repair and/or replace when that time comes–around 250,000 miles on average.  Furthermore, if you intend to use the truck for running errands around town, and only plan to tow on rare occasion, you would likely be better of with a gas engine.  Gas engines handle the shorter distances and frequent starts of the “around-town” truck better.

Diesel engines, on the other hand, provide some serious horse-power.  If you are looking to tow more than 12,000 lbs on a regular basis, you will want to consider a diesel.  While diesels also come with automatic and manual transmissions, most frequent-haulers prefer manual as the transmissions are simpler, more reliable under heavy strain, and cheaper to repair.  As a whole, diesel engines run more efficiently and more reliably than gas, which is why they are so popular with commercial haulers.  Diesels, as a general rule, are not expected to require extensive repair or replacement until they have around 500,000 miles (or much more) behind them, giving them the nickname “million mile engines.”  The downside is that when that repair/replace time does arrive, it is going to cost you seriously–about twice as much as for a gas engine.  These days, diesel is also quite a bit more expensive than gas in most states, which may cause your monthly upkeep expenditure on the truck to increase significantly.  In addition, a diesel engine is designed to run hot.  In other words, you do not want to use it to run errands around town if you can help it.  It is designed to pull, to work under heavy stress and strain, to drive long distances, and to run for long periods of time.  If you need to drive out to your hay field just to toss some bales into the bed, with a gas engine, it would be more efficient to turn the engine off while you load.  With a diesel, though, you would want to leave it running while you load those bales, and allow the engine to get hot as it sits.

Of course, you’ve probably figured out by now that the choice isn’t as cut and dry as “gas or diesel?”.  There are other considerations involved before you decide.  We found that, as a whole, gas engines were generally less risky when purchasing used vehicles.  For the most part, gas engines have been around forever, and only little changes and improvements have occurred throughout the years.  This fact has kept the engines pretty consistent.  Replacement parts and mechanics are more widely available and more affordable.  If you happen to be a Toyota fan, the gas-powered Tundra is your truck, with a newly introduced max. towing capacity of 10,400 lbs.

On the other hand, diesel engines have changed significantly over the years, different manufacturers have developed different parts that are then assembled by other manufacturers, and much of the diesel industry has been unionized, which has caused it’s own issues.  As you get into the research, it becomes clear that diesel engines vary with the year they were made, and the company that made them or their parts at the time.  We didn’t do much research prior to about 1997, but the following is a summary of what we found regarding the diesel engine after that time.  Please understand that these statements are generalizations based on our research of auto websites, and discussions with manufacturers, dealers, and owners.  There are exceptions in every case.

The first diesel issue we found was with Ford.  Mind you, my family has had a multi-generational boycott of Ford for several reasons, but seeing as how we found them to be more affordable and easier to come by, we were giving them as much consideration as any other brand.  Essentially, from about 1997-2003.5, Ford made an incredible 7.3L diesel engine that buyers absolutely loved.  It was considered THE engine to have, it was durable, reliable, long-lasting, and had minimal issues.  In 2003, however, new emissions standards caused a re-design of the engine.  At the same time, there was a labor dispute with the engine manufacturer that resulted in a bit of unplanned-for “tweaking” by the cylinder makers to the new 6.0L diesel that was introduced that year.  This resulted in an engine that had quite a few problems with the cylinders, and quickly resulted in an unpopular, and quite undeserved, reputation for Ford.  Once Ford discovered the source of the problem around 2006 (when the increasing miles caused the cylinders to fail), they quickly fixed it.  However, it still took several years to correct the majority of the bad engines out there (and some still aren’t fixed).  The stressors of the engine problems also caused many transmission issues around the same time.  That same year, an improved engine was introduced, which hasn’t had nearly the troubles.  Nonetheless, despite the steps Ford took to extend warranties and correct the bad engines, their reputation took a bit of a hit.  Since 2006, however, their engines have made a come-back, and their reputation for quality and reliability are improving.  Every mechanic and dealer we spoke with, though, agreed that the best Ford engine ever made was the 7.3L diesel.

Chevrolet hasn’t been without it’s problems either.  In 2001, Chevy introduced the 6.6L Duramax engine, but it quickly revealed an injector problem.  As a result, Chevy warrantied those engines to 200,000 miles for the injectors, and by 2004, had fixed the problem internally.  If you find a Duramax from 2001-2004, make sure the injectors have already been replaced, or you may be risking a costly repair.  We encountered a number of die-hard Chevy fans who wouldn’t own anything else.  The Chevy mechanics and dealers we spoke with also seemed to conclusively agree that the Duramax was an excellent diesel engine.

Dodge engines, overall, seemed to be a really good engine, whatever year they were made.  The year 2003.5-2004.5 was considered a great year, though, with an engine that could provide 325 horse-power and tow a significant amount. A big advantage of the Cummins diesel engine is that it doesn’t have glow plugs, like other diesel engines.  It has a grid heater that apparently is more reliable and less costly to replace.  In a cold climate (less than 20*), glow plugs seem to work more effectively, so a block heater would be a necessity for a Cummins.  Otherwise, though, most experts we talked with agreed that Dodges were just generally good, reliable, durable engines, that held up well under stress.  The downside of the Dodge, according to all the data we read, was that their tow capacities couldn’t touch the Chevy’s and Ford’s maximums–especially in the goose-neck department.  So, if you prefer a diesel, but only need to haul up to about 14,000 lbs, you’d possibly be very happy with a basic model Dodge 3500.  If you need to haul more weight than that, you may want to consider another truck, though.

As a quick note, whether you use gas or diesel, both use the same transmission.  The transmissions can have just as many issues as the engines, and often need repair/replacing around 200,000-300,000 miles, regardless of the engine it’s paired with.  It’s something to consider any time.  A transmission is heavily stressed under towing conditions, though, so if you are buying a used vehicle, the less towing it has done, the better chance it will last for more miles after you buy.

A great precaution we discovered when buying a used vehicle–especially one with higher miles–was to utilize the manufacturer’s internal database.  When you find a used vehicle you are interested in, you can take the VIN into the parts/service department of your local dealer for that make of truck and ask for a vehicle service history.  In about 60 seconds, they can print off a list of all recalls for that vehicle, and all services that were provided by manufacturer-authorized service stations.  It is possible that something was fixed that was not warrantied or by an independent mechanic, in which case, it wouldn’t be recorded.  However, most of the recall-related issues on the list would be covered under warranty, and therefore would likely be reported by a mechanic that did the repair, in order to get paid by the manufacturer.  That list was extremely handy for us, and was what eventually helped us find our truck in the end.