Upper Cylinder Lubricant

An instantly popular low cost product that offers long term engine protection benefits. Buy a case and use every other tank. Fills the gap in the engine where your motor oil can’t go. Check out the reviews below.

Preserves Horsepower and Performance

Upper Cylinder Lubricant, 6 oz. bottle

Your engine’s top-end is sparsely lubricated and prone to the development of performance-robbing deposits. It’s also highly susceptible to corrosion, an issue compounded by the prevalence of ethanol in today’s fuel. AMSOIL Upper Cylinder Lubricant is designed to solve those issues. Its AMSOIL-exclusive, powerful formulation helps maximize engine power and performance while increasing engine life. And unlike competing fuel additives, AMSOIL Upper Cylinder Lubricant works.

Lubricates Top-End Components

The intense heat of combustion and limitations of the oil-control piston ring result in a lack of oil at the top of each cylinder. AMSOIL Upper Cylinder Lubricant’s unique additives provide that missing lubrication to fight piston-ring and cylinder wear, maximizing engine compression and horsepower. Its lubricity improvers also aid in protecting fuel injectors and other fuel-system components from wear, helping ensure excellent performance and long-life. AMSOIL Upper Cylinder Lubricant delivers 18 percent more lubricity than Lucas* and 20 percent more than Sea Foam* for better retention of horsepower and fuel economy (see chart below).1

Buy & Check PriceAnd Container Size

Popular with our customers who do a lot of driving and may want to take a car well past 200,000 miles.

Download Printable Product Data Bulletin

Download PDFProduct Datasheet

Well stocked in the Omaha store at 84th & G.

AMSOIL Upper cylinder Lube Inhibits Corrosion

Another AMSOIL Exclusive

Upper Cylinder Lubricant uses potent corrosion inhibitors to coat metal surfaces, block out moisture and stop deterioration before it starts. This is particularly important when using gasoline that contains ethanol due to its propensity to attract water and hasten corrosion. Inhibiting corrosion maximizes component life and reduces wear in the engine’s top-end to guard against compression loss and maintain optimum power.

  • Lubricates fuel system and upper cylinders
  • Fights ethanol-related corrosion
  • Helps keep injectors clean
  • Compatible with capes fuel systems

Keeps Injectors Clean

Upper Cylinder Lubricant contains detergent additives designed to maintain injector cleanliness. While AMSOIL P.i. Performance Improver is designed to attack and remove stubborn injector deposits that can reduce power and fuel economy, Upper Cylinder Lubricant helps preserve injector and combustion-chamber cleanliness. Using it with every tank of fuel helps retain fuel-economy and performance gains and maximizes component life.

Capless-Compatible Packaging

Many new vehicles have replaced traditional fuel caps with capless systems. The threads on most bottles restrict them from opening the flap inside the fuel neck and make removing the bottle difficult. The AMSOIL Upper Cylinder Lubricant bottle is fully compatible with capless fuel systems. It’s easy to insert, pour and remove the bottle.


  • For use with cars and trucks.
  • For best results, use with every tank of fuel. Do not refill tank until almost empty.
  • Treats up to 25 gallons. Add entire bottle to tank at fill-up.
  • Treat large gas tanks with two bottles of Upper Cylinder Lubricant. Using more than two bottles is not recommended.
  • Safe for use with catalytic converters, oxygenated gas and up to 15 percent ethanol-blended fuels. Do not use with E85 fuel.
  • Do not use with two-stroke or diesel engines.


AMSOIL products are backed by a Limited Liability Warranty. For complete information visit www.amsoil.com/warranty.aspx.


This product is not expected to cause health concerns when used for the intended application and according to the recommendations in the Safety Data Sheet (SDS). An SDS is available at www.amsoil.com or upon request at (715) 392-7101. Keep Out of Reach of Children.


1 Based on independent testing of AMSOIL Upper Cylinder Lubricant, Lucas Upper Cylinder Lubricant and Sea Foam Motor Treatment obtained on 02/13/2019 using the ASTM D6079 modified for use with gasoline. *All trademarked names and images 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. All products advertised here are developed by AMSOIL for use in the applications shown.


Upper Cylinder Lube Reviews


Better Gas Mileage

By  NICK,  a  Verified Buyer  from  Greeley,CO  on  December 13, 2023
Notice I get better fuel mileage. Use my Subaru for package deliveries and I can see the difference in the bank account, less on gas!

My favorite gasoline shot

By  Nathanael,  a  Verified Buyer  from  New Jersey  on  December 04, 2023
I use this product frequently, it gives me peace of mind that the upper components of my cylinder head are lubricated giving longer life to the engine in the long run.

Keeps GT Mustang running smooth

By  JAMES R,  a  Verified Buyer  on  December 02, 2023

When not using performance improver PI I use this in every tank in between
Editors note: – Using the UCL (Upper Cyl Lube) you could easily spread out the PI use doubling the recommended span as the UCL prevents the deposits if using at least every other tank.

Outstanding Upper Cylinder Cleaner

By  RICH,  a  Verified Buyer  on  December 01, 2023
Once again I find Amsoil to be superior. I have used this consecutively for five months and found that my valves were way cleaner after use, than prior to using this product. If I can see what five months has done, imagine a year of using this product and how it would keep them clean. Thank you Amsoil. I would seriously recommend using this as a preventive measure monthly.

It’s Getting Pricy????

By  KENNY D.,  a  Verified Buyer  from  San Jose California  on  September 28, 2023
$66.11 a 12 Pack Delivered. That’s $5.50 a Bottle! (NEARLY A DOLLAR AN OUNCE)????? It’s getting to be Pricey here at AMSOIL…. At this point this is the only product that I can just Barely afford to KEEP Purchasing. And it has gone up in Price substantially in the last # of Month’s. I think AMSOIL is a GREAT Product, But The Price Point is Getting to be Outta Control, to the Point I may not be able to keep purchasing here. It’s definitely a crying shame to say the very least. I use it Every Tank if I remember to Bring a Bottle with me to the PUMP. The Cap seal is still a PITA, but It’s gotta be sealed so whatever there. We’ll see what happens here, If the Price goes up much more, I’ll be forced to purchase elsewhere. And that makes me very SAD. I’ve been with AMSOIL since 1997!!!! “26” YEARS…. ??…..
Editors note: The reviewer was paying full retail. Naturally AMSOIL doesn’t control inflation but we can help! If you call me directly at 605-274-2580 I can save you quite a bit on the case. If you don’t mind calling you DO save more but online even the preferred customer pricing which you can do online, you will keep the per bottle cost under $5 when buying in the case not to mention added perks.

Top End

By  CHARLES F,  a  Verified Buyer  from  Arlington, TX  on  September 18, 2023
Great product for upper cylinder. Tops Lucas.

Cylinder Lubricant

By  CHUCK O,  a  Verified Buyer  from  Oklahoma  on  August 28, 2023
I have been using Amsoil Upper Cylinder Lubricant for years and have not experienced any engine malfunctions what so ever. Extra protection is never a bad idea.

Best there is!

By  Gary,  a  Verified Buyer  from  Flowery Branch Ga  on  July 24, 2023
This fuel additive is the best! Tried it in my CRV & Odyssey van mileage improved 2mpg, engines idle smoother.