Customer Ratings & Reviews

Great product easy maintenance item

Been using this stuff for two three yrs now seems to be working fine no problems

I’m an Amsoil preferred customer for many years. If they have a product that meets or exceeds specification it is what I buy. I’ve observed first hand the results of using their products and in my opinion there are none better.

Will be trying this one out for the first time. If it works like all the others, it will be outstanding.

So I have had 12 of these I put one in every other fuel fill up and I see the difference with my truck. I have really notice it on my girlfriends suv who suv is 2017 and it has a big difference in it. Hers is a Stinking Chevrolet.

Helps my 2010 Honda fit keep ticking after 160 thousand miles.

I can hear a noticeable reduction in valve train noise after using this additive. The engine seems to run smoother especially when used in combination with P.I Performance additive.

Amsoil has the best products around.

We have a 2013 Mercedes S550. My normal highway mileage from Sacramento CA down I-5 to Orange County with the Cruise set at 75mph normally gets me a squeek under 27MPG. I though I would try some of this Upper Cylinder Lubricant on our trip to Wichita KS going the upper route of I-80 then down to Denver and across on I-70 to Wichita. This time with the cruise set at the speed limit indicated (70-75 or-80), I was enjoyably surprised to consistently be coming in at 28.5+ mpg per tankful- both East as well as West bound on the same route. When I got home, I ordered 2 more cases right away and have been using it most every tankful now.

Bought a case about 2 months ago, I fill up once a week, the engine has been smoother and definitely more power and better performance, being consistent on using it for every fill up makes the biggest difference. I’m now on 5th fill up using one per fill up and stayed back to back consistent using it and love the performance in my Lexus is250

I can feel the pickup or snappy response. This is the best.

Awesome product

I very much recommend AMSOIL products.

You will feel the added power in the engine when this product starts cleaning and lubing the upper portions of it.

A must have now a days in 2022 with the so such bad gas around having atleast fifteen plus percent ethanol in it.

I think my engine is just a bit quieter when idling when I use this product.

I began using Amsoil Upper Cylinder Additive after I had an Amsoil oil change done to 2019 Lincoln MKC 2.0T. I don't really know by seeing that it works but by feeling the performance. I am very confident in it's conditioning regarding the upper cylinder, the turbo and all the components that have a say about how the vehicle will run. We just bought a 22 Hyundai Santa Cruz Limited 2.5T and I will add the product to my first fill up. Do yourself and your second best friend ( married know it's the spouses ) your car; whatever his or her names they may be; a lifeline such as Amsoil products. Also as a tip go to You Tube for the Amsoil vs Major name oil comparison testing I was amazed!

Will buy again

This additive works great cleaning & lubricating the intake valves

Removes knocks