As modern car manufacturers trend more towards high efficiency vehicles every day, diesel cars are becoming increasingly common. While diesel power has been a mainstay for large trucks for decades, economy car manufacturers simply have not been able to ignore the efficiency advantages that diesel engines boast, so it comes as no surprise that we are starting to see more and more small displacement diesel economy cars on the road as well.
However, as engine efficiencies go up, auto manufacturers are extracting ever more power out of ever smaller packages. While these engine use less fuel, the tradeoff is that internal engine components (and components in your fuel system) have to withstand significantly more abuse, higher forces, and higher heat. In light of this, whether you drive a large displacement dually to tow your boat or a fuel sipping econobox as you whiz by gas stations, there is no question that it is more important than ever to maintain your car’s engine and fuel system.
One easy method to help keep your diesel fuel system as well as certain internal engine components healthy is with occasional use of a diesel fuel additive. To use a diesel fuel additive, you simply buy a bottle and pour it in your tank during fill up every once in a while. In most cases, every 3-6 months is often enough depending on how much you drive, but some particularly diligent folks will go so far as to use a bottle during every fill up (which we think is a waste of money to be honest).
Why Use A Diesel Fuel Additive?
Diesel additives do a number of desirable things that help your fuel system and engine function better. For starters, they lubricate your fuel system components such as bearings (in your pumps), o-rings, and seals which can help extend the life of things like your fuel pump. Diesel additives also promote better and more complete combustion of the fuel, which means that your vehicle will operate more efficiently. Next, like the best fuel injector cleaners, diesel additives clean your injectors to improve spray pattern and fuel atomization which results in more complete fuel burn and higher efficiency (as well as smoother idle, better running and better performance). Finally, additives can make cold starting easier in the winter.
The Best Diesel Fuel Additives
When it comes to choosing the best diesel fuel additive, there are tons of options. In reality, you’ll likely get as many opinions as there are brands on the market. In hopes of making your life a little bit easier, we have chosen a few of our favorites to help you make an informed decision.
Power Service Diesel Kleen +Cetane Boost
Our favorite diesel fuel additive is the Power Service Diesel Kleen +Cetane Boost. This additive package has a number of benefits for your diesel car or truck that make a difference in the way it runs and performs.
For starters, it is capable of cleaning and lubricating your fuel system components, such as your fuel pump and fuel injectors. Keeping these components operating in tip top shape will keep your idle and acceleration nice and smooth without any hesitation or misfiring. The lubricating properties also work to prevent injectors from becoming stuck. In addition, Power Service’s trademarked Slickdiesel lubricant also protects your fuel system components from the increased wear associated with using ultra low sulfur diesel (ULSD) which is commonly found these days in gas stations.
Another facet that makes Power Service’s additive one of the best diesel fuel additives on the market is that it is safe for use on all types of diesel engines. This means that it will also work effectively in a biodiesel system as well as a blended biodiesel system in addition to conventional diesel powertrains.
Another benefit to Diesel Kleen is the cetane boost. Cetane to diesel is similar to octane to gas…sort of. For gasoline, higher octane means increased resistance to ignition which allows the fuel to be run in a higher compression setting. In diesel, cetane is quite the opposite. Increased cetane results in a fuel that is easier to ignite. Based on the way a diesel engine works, you want your fuel to ignite easily and quickly, so added cetane will accomplish this. Increasing the cetane level also tends to increase efficiency and power, and as such adding Power Service’s product to your fuel tank will result in a small but noticeable bump in power and slight decrease in fuel consumption.
Overall it’s a tremendous product and the first one we’d recommend trying out.
Sta-Bil Diesel Formula Fuel Stabilizer and Performance Improver
Another favorite diesel fuel additive of ours is the Sta-Bil Diesel Formula Fuel Stabilizer and Performance Improver. The benefits of this additive package are slightly different than the Power Service reviewed previously. This additive is more focused on fuel stabilization, meaning that it will come in handy if you are trying to store your vehicle for an extended period of time but still intend to start it up every once in a while.
Like Power Service’s additive, the Sta-Bil will also lubricate critical fuel system parts when used. Additionally, it will also clean dirty injectors to promote more even spray patterns and better fuel atomization.
When storing your car there a few challenges that Sta-Bil works to address. First, leaving fuel sitting for a long time allows particulate to settle out, ultimately creating sediment and sludge that can clog fuel filters and wear your fuel system. If this happens, the solution is typically to replace your fuel system components and fuel hoses at significant cost. Fortunately, using a product like Sta-Bil as a preventative measure means that you won’t have to worry about these things.
Another challenge is that diesel fuel oxidizes over time, which results in inability to start your car if it has been left sitting for a while. Sta-Bil again works to prevent this. Additionally, it prevents microorganisms from growing in your fuel tank including bacteria, algae, and fungi. While this sound like an unlikely problem, you’d actually be surprised how resilient some microorganisms can be…they can even survive in an environment as harsh as a diesel fuel tank!
Overall, we give Sta-Bil a nod because we think you will find that the Sta-Bil is a great diesel fuel additive that will easily prevent any problems when storing your vehicle. It’s worth a look.
Hot Shot’s Secret Diesel Extreme
While Sta-Bil and Power Service are more well known brands, Hot Shot’s flies under the radar for the most part. That said, they make a pretty solid diesel additive that is worth checking out. Like the Sta-Bil and Power Service, the Hot Shot’s helps to clean out your fuel system. It also lubricates moving components within your fuel system such as your pump which extends fuel system life.
The Diesel Extreme also acts as a fuel stabilizer by neutralizing water within the fuel, which is a big contributor to corrosion if you let your car sit. In addition, it also works to prevent rust by lining the metal components of your fuel system (such as your fuel tank) to prevent oxidation.
Perhaps one advantage it has over the Sta-Bil is that it is a cetane booster (like the Power Service), which helps to increase both performance and efficiency by allowing for easier fuel ignition. Like the other two, it is extremely easy to use. Simply pop your gas cap next time you fill up and dump the mixture in your tank using your desired ratio (Hot Shot’s provides recommendations for amount depending on what you’re trying to do). A good rule of thumb is two gallons of fuel to one ounce of diesel fuel additive.
Overall, the Hot Shot’s is a bit of a dark horse in this lineup, meaning that while you may not expect it, it’s a really great product. As such, we give it a strong recommendation!
So there you have it, hopefully this article has provided you with some guidance as far as where to find the best diesel fuel additives. As far as where to buy, Amazon typically offers highly competitive pricing that makes them a good place to buy. While we have our preferences, it’s important to note that there are many great products out there from other manufacturers…Redline, Royal Purple, Stanadyne, Liqui Moly, and Lucas are a few more runner ups that come to mind. If you find that our above recommendations don’t quite suit your needs, feel free to have a look at other diesel additive products available by clicking here. Happy wrenching!