Customer Ratings & Reviews

Will buy again

This additive works great cleaning & lubricating the intake valves

Removes knocks

I notice at least 1 to 2 miles better per gallon when I add this to a tank of fuel truck runs great only use regular fuel no pain no hesitation works as advertised

I believe in UCL. When you think about highly-humified air sitting in the upper cylinder, cooling, and water condensation, UCL totally makes sense. Add to that keeping the valves clean and better gas mileage. Maybe why my Hemi has 71K and runs like day 1 with zero smoke?? I'm convinced. The bad part is the awful seal, hence the 4 stars. Why not a pull tab like was on these bottles for a short while...like every other sealed bottle in the world??

Great results.

Seems to work great! I use it every tank. Then once or twice a year I use P.I. on one tank keep everything clean.

My engine would sometimes tick at startup and occasionally even a small puff of smoke from exhaust. I now use upper cylinder Lubricant at every fill up and have noticed no smoke or ticking on startup. Good stuff! My research online seems to be that without zinc in todays fuels that the cam lobes wear after while and is not a reversible situation. I am on my third case and seems to be satisfactory results so far.

2016 f150. Truck runs smooth. Amsoil just make the best. All I can ask is that my truck keeps going, and Amsoil makes sure it does.

I recently purchased a new Benelli motorcycle. After the 700 mile break in period, I changed the engine oil to Amsoil and decided to start using the upper cylinder lubricant fuel additive. Bike performs well, sounds great and maintains even engine temperatures. I also made a trip to South Dakota and back, adding this to every tankful. Good stuff!

Started using this product more regularly in between cycles of the PI additive. Have definitely noticed better maintained fuel mileage in between oil changes when using this.

I have been a Preferred Customer for years. Using Amsoil products saves time and money vice having all of ths work done at a shop, and especially at a dealership. I have a long drawn story I tell people all of time about how I discovered Amsoil and why I have these products for so long. Just not enough room here. I enjoy and trust Amsoil products in all of my vehicles and equipment. 2 trucks with over 250, 000 miles each that I owned for 14 years each and working on third, plus my wife's cars and kids vehicles and 6 grown grand kids (hopefully I will be around to help some of my great grandchildre of which I have seven.

Gas mileage just gets better

Great product to keep my injectors clean and help minimize fuel system damage from ethanol

Time will tell.

This has improved my Subaru fuel mileage. We went from 22mpg average to 25!

Working as advertised First use was in conjunction with the PI fuel system cleaner and every tank since has been pretty much been dead on the 25% increase in combination city highway driving for me those far The highway mileage in my vehicles has returned to the original manufacture numbers the improvements from this product have been welcomed greatly with the current fuel prices

I used this with the P.i. performance improver gas additive and actually improved my M.P.G. I will use this combo from now on. A noticeable improvement

Upper cylinders on a lot of vehicles don't get the lubrication they need with ordinary fuel treatments. I've used this for several years now, and notice my vehicles run smoother and respond better prior to have not using this product.

Tune up time for C2500 and Jeep Cherokee.