
- One ounce treats up to 2.5 gallons of fuel
- Combines the benefits of AMSOIL Diesel Injector Clean, Diesel Cold Flow and Diesel Cetane Boost in one convenient package
- Delivers outstanding detergency, improved lubricity, better cold flow and higher cetane
- Provides excellent all-season protection and performance
- Provides significant lubricity improvement in diesel fuels found across the U.S., delivering improved wear protection.1
*All trademarked names are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use.
1Fuels tested in 2017.
Product Overview
Specially engineered to provide exceptional all-season protection for a serious performance boost. One dose delivers outstanding detergency, improved lubricity, better cold flow and higher cetane.
CLEANS, PROTECTS AND RESTORES POWER
- Cleans dirty injectors
- Restores power and torque
- Reduces smoke and emissions
- Combats fuel-system corrosion
- Provides significant lubricity improvement in diesel fuels found across the U.S., delivering improved wear protection.1
1Fuels tested in 2017.
AMSOIL Increases Lubricity
Testing reveals AMSOIL Diesel 4-IN-1 provides significant lubricity improvement in diesel fuels found across the U.S., delivering improved wear protection.OO

OOFuels tested in 2017.
SUPERIOR COLD-TEMPERATURE PROTECTION
- Lowers cold filter-plugging point (CFPP) by up to 40°F (22°C)
- Enhances engine reliability in cold temperatures
- Improves low-temperature startability
- Prevents wax settling during storage
IMPROVES FUEL QUALITY
- Increases cetane up to 4 points
- Delivers maximum horsepower
- Increases fuel economy up to 8%
- Improves startability
- Smooths idle
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Product information checked: September 2026. Product formulations, specifications, applications, availability and published claims can change.
For the latest official information, consult the AMSOIL Corproate Website.




