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AMSOIL Fuel Additives
Delivers confidence in your diesel's performance. Concentrated formula uses unique chemistry to target and eliminate specific performance issues, maximizing diesel power.
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| Product code | Package size | Unit of measure |
|---|---|---|
| ACBCN-EA | 16 oz. | Each |
| ACBHG-EA | 64 oz. | 64 oz. |
| ACBCN-CA | Case of 12 16 oz.s | Case of 12 |
| ACB05-EA | 5 Gallon Pail | 5 Gallon Pail |
| ACB55-EA | 55 Gallon Drum | 55 Gallon Drum |
AMSOIL Diesel Cetane Boost (ACB) is the standalone cetane number improver for diesel engines that need higher-cetane fuel than the pump provides. The concentrated formula raises the cetane number of treated diesel fuel up to eight points for maximum horsepower, increased fuel economy, and easier starts. It is built for heavy- and light-duty diesel pickups, fleet trucks, agricultural and construction equipment, marine diesels, and tuned applications running modern emissions hardware.
Cetane number measures how quickly diesel fuel ignites under compression. Higher cetane shortens ignition delay so the fuel burns sooner and more completely, producing more usable power per stroke. Diesel engines operate best on fuel with a cetane value of 50 or higher, but most diesel sold in North America has a cetane value of 40 to 45. Diesel Cetane Boost closes that gap by raising the cetane number of the treated fuel up to eight points. A four-point lift is also available at half the dose, useful for short trips or fuel that already runs closer to specification.
Fuel with a higher cetane number provides for a more complete burn, which leaves less unburned fuel behind to exit the engine as visible smoke or particulate. Diesel Cetane Boost improves the ignition quality of diesel fuel, smooths idle, reduces smoke and emissions, and helps the engine recover the available power that low-cetane fuel can mute. Drivers chasing throttle response, quieter idle, or reduced visible exhaust at light load are the primary buyers for ACB.
Short ignition delay also matters at low ambient temperatures, when cylinder walls are cold and the air charge is harder to autoignite. Higher-cetane fuel lights off faster, which shortens cranking time, reduces the cold-start white smoke that comes from unburned fuel, and lowers stress on the starter and batteries. Cold-weather diesel pickup owners, fleet operators, and equipment that sits between starts are common users.
Diesel Cetane Boost is excellent for use with ultra-low-sulfur diesel fuel (ULSD) and is compatible with biodiesel and all types of exhaust emission systems, including diesel particulate filters (DPFs). The formula is alcohol-free, so it does not introduce ethanol or methanol into a diesel system that was never designed for it. The product is recommended for use in all types of heavy- and light-duty, on- and off-road, and marine diesel engines.
Diesel Cetane Boost is the cetane-number specialist in the AMSOIL diesel additive line. It is excellent for use with AMSOIL Diesel Injector Clean for fuel-system cleanup and lubricity, and with AMSOIL Diesel Cold Flow for cold-weather gel and wax protection. The three additives can run in the same tank when more than one issue needs attention. ACB is the right choice when the priority is cetane only.
Add Diesel Cetane Boost before filling the tank so the inflowing fuel mixes the additive. Treat every tank for consistent benefit. The chart below shows the dose for a four-point or an eight-point cetane increase across common fuel volumes:
Diesel Cetane Boost can be combined with AMSOIL Diesel Injector Clean and AMSOIL Diesel Cold Flow in the same tank for broader fuel-system care. Aftermarket cetane-only additives are not necessary alongside ACB.
| Fuel volume | Additive for 4-point cetane increase | Additive for 8-point cetane increase |
|---|---|---|
| 5 gal | None | 1 oz |
| 10 gal | 1 oz | 2 oz |
| 30 gal | 3 oz | 6 oz |
| 80 gal | 8 oz | 16 oz |
Diesel Cetane Boost is available as a 16 oz bottle (ACBCN-EA), case of 12 16-oz bottles (ACBCN-CA), 64 oz bottle (ACBHG-EA), 5 gallon pail (ACB05-EA), and 55 gallon drum (ACB55-EA). All AMSOIL lubricants and fuel additives are backed by the AMSOIL Limited Liability Warranty. Match the right diesel oils, filters, and additives for the engine with the AMSOIL Diesel Oil Guide, match the right product in the AMSOIL Vehicle Lookup Guide, then order AMSOIL Diesel Cetane Boost.
Our 2020 RAM Limited was slowly becoming less fuel efficient. We were in the Mid teens for fuel mpg lately! A customer recommended your brand. So, I tried it last week and now my fuel economy has gone back up to the low 20 mpg range once more!
Would recommend this to a friend.
Seems to make my boat run better with less smoke.
Would recommend this to a friend.
Aids is helping keep diesel fuel system clean and in cold weather starts( below 20 degrees F)
Would recommend this to a friend.
A cetane improver works by shortening the ignition delay of diesel fuel after it is injected into the cylinder. Diesel engines run best on fuel with a cetane value of 50 or higher, but most North American pump diesel measures 40 to 45. Diesel Cetane Boost raises the cetane number of treated fuel up to eight points, which produces a more complete burn, smoother idle, easier starts, and recovered horsepower and fuel economy that low-cetane fuel can mute.
For a four-point cetane increase, add 3 oz to 30 gallons. For an eight-point cetane increase, add 6 oz to 30 gallons. The 16 oz bottle treats up to 160 gallons at the four-point rate, or 80 gallons at the maximum eight-point rate. Add Diesel Cetane Boost before filling the tank so the inflowing fuel folds the additive into the load.
Yes. The formula is excellent for use with ultra-low-sulfur diesel fuel and is compatible with biodiesel and all types of exhaust emission systems, including diesel particulate filters. It is alcohol-free, so it does not introduce alcohols into the fuel system or downstream catalysts.
Higher cetane shortens ignition delay and generally produces a quieter, smoother burn rather than a louder one. The treat chart on this page was developed around the eight-point maximum lift, so following the labeled dose keeps the fuel inside the cetane range modern diesels are engineered to run on. Use the recommended rate rather than overdosing the tank.
Diesel Cetane Boost is the dedicated cetane number improver. AMSOIL Diesel Injector Clean targets injector deposits, restores fuel atomization, and adds lubricity for fuel-system protection on ULSD. AMSOIL Diesel Cold Flow targets gel point and wax precipitation in cold weather. The three additives can be used together in the same tank when more than one issue needs attention.
Diesel Cetane Boost is recommended for use in all types of heavy- and light-duty, on- and off-road, and marine diesel engines, which covers Cummins, Power Stroke, Duramax, and Mack heavy-duty platforms, plus older diesel pickups, agricultural tractors, and stationary equipment running pump diesel.
No. Using AMSOIL synthetic lubricants and fuel additives does not void a new vehicle or equipment manufacturer warranty, and AMSOIL fuel additives are covered by the AMSOIL Limited Liability Warranty.