5 Diesel Fuel Additives Truck Drivers Swear By

Drivers trying to get the most performance out of their diesel trucks — and there are many things you can do — will sometimes resort to fuel additives. Diesel fuel is given a cetane rating during its refining process, a number that typically falls between 48 and 50, and additives could increase that number. Lower numbers mean the fuel has a longer ignition delay, which no driver wants. The idea is that raising the cetane rating would increase the ignition speed and also act as a lubricant for the rest of the system's components. Keep in mind this isn't the same thing as the octane number at the gas pump. It could be worth a try if you're on the fence, as you'll find it difficult to damage your engine by using an additive. 

All the additives on this list are available at Amazon but can also be found in retail stores if you don't want to wait for shipping. Along with that, all five have high user scores backed up by hundreds of reviews. A more in-depth explanation of how these additives were chosen can be found at the end of the list.

The Lucas Oil lubricant is a popular choice among users thanks to its easy availability and the fact a small bottle of it typically costs about $15. It bills itself as something that's able to work with gas and diesel, and the bottle tells you to use it on every fill-up. It's comprised of a blend of detergents and additives that are designed to neutralize sulfur and other harmful things that can shorten the life of your fuel system parts. Over time, the Lucas Oil lubricant promises to prevent rust and corrosion, thus extending the life of your components.

If you're looking to buy in bulk, you can grab a gallon of it on Amazon for $31. It's clear it's doing something right among buyers because it holds a 4.8 out of five rating based on over 20,000 reviews. Despite the high scores, some reviewers have noted they haven't noticed better gas mileage even though there are other improvements like less rattling and lower oil consumption.

If you're looking to boost gas mileage, the Hot Shots Secret Everyday Diesel Treatment says it'll be doing just that. It says it increases the cetane level up to seven points, and that will, in turn, give you better mileage over time. On top of that, you'll get lubricant that helps protect your fuel pump and injectors. Unlike some of the other options, this additive is made for just diesel, so make sure you don't put it into your regular gas tank.

This is another highly reviewed product on Amazon, as it holds a 4.8 out of five rating with over 6,800 reviews. You can pick up a 16-ounce container for $18, or you can opt for a gallon for $72.99. This makes it far more expensive than other options on the list, so you'll need to weigh your options and decide whether you're ready to splurge on something like this. If you do end up buying it, you can rest easy knowing it's the top-rated diesel additive on Amazon.

Stanadyne has a popular diesel additive that claims tests show an average of 4% improvement in miles per gallon, and the company says that number can go up to 9.6%. On top of improving gas mileage, it says it reduces wear on your parts and cuts back on emissions, so it offers a lot the other additives do. You can pick up a half gallon of Standayne's Diesel additive on Amazon for $36, where it has a 4.8 out of five rating based on over 600 reviews. This puts it on par with many of the other additives on the list, and many of the reviewers have nothing but positive things to say.

However, a downside is some people say they haven't noticed gas mileage getting better in a noticeable way, and it's tough to tell if your parts are lasting longer without taking anything apart. This half-gallon jug treats up to 240 gallons of fuel, so you should be able to get many uses out of it to determine if it's making any difference.

For $42 from Amazon, you can get a 40.6-ounce container of Archoil's Diesel Treatment, or you can opt for a two-pack and get them for $75. This will treat up to 400 gallons of diesel fuel, so you'll get plenty of uses out of it to help justify the high cost. As for what it brings to the table, it's about the same as you'd expect from additives of the sort, as it promises better mileage and protection for your fuel system. This works for all diesel vehicles, and you'll want to make sure you don't put it into a regular gas car as it won't work with both.

Archoil says customers will see an increase of 10% in their fuel mileage, and some reviewers do note they've seen an uptick in mileage and their truck idling better. Your mileage will vary, but there are a lot of happy campers with this additive. This product has a 4.7 out of five rating on Amazon with 900 reviews and counting.

A budget-friendly Diesel additive is the Howes Diesel Treatment, as a half gallon of it costs $14 from Amazon. Despite the lower price, it does mostly everything the other additives promise by preventing fuel injector deposits from forming. All of this is done to help prevent your parts from wearing out as fast as they would otherwise. This formula also promises to stop the diesel fuel from gelling up in the winter. What it doesn't advertise is giving you better gas mileage, so this isn't an additive you'd want to pick up if that's what you're looking for.

The user scores for the Howes Diesel Treatment are 4.7 out of five on Amazon, with over 1,900 reviews. With this one not promising to add gas mileage, the results are easier to see, and people do report back saying the fuel didn't gel. Some people say the additive itself can freeze, however, so make sure you're not leaving it out in sub-zero temperatures.

Every diesel additive found on this list has high user scores — all 4.7 out of five or higher on Amazon. This makes it so all of the options are loved by users, even if it's difficult to tell if the additives are doing their job. Depending on who you ask, they are either essential or useless. In the end, it doesn't hurt to try out an additive as you're not going to damage parts of your car by doing so, and the results could certainly work in your favor.

The long-term effects of diesel additives have been murky, and there's not a whole lot one way or another proving whether the additives are worthwhile additions. Nevertheless, many drivers swear by them, and there are a lot of different products on the market to add to your diesel fuel. At the very least, you're not going to be breaking the bank by trying one out.