Customer Ratings & Reviews

I use this with my all my vehicles. Great product and great price. Wish it was just a bit easier to get the white seal off the top of the bottle. It's still the best.

If this was made by anyone else I probably wouldn't buy it. But I have confidence in Amsoil, and I trust their products because my vehicle has started running better, and shifting better with the Signature Series transmission fluid which has outperformed the Mopar 8-9 speed fluid I used to run in my Jeep. Great company making great products.

I started using it my 2017 Tundra and increased the fuel mileage by 1.5 miles and the power is crazy ridiculous now. Sold on it and used it in my Can Am side by side too. It is quieter and smoother running

I use this with every non tier fill up and for all extended road trips.

Honestly you can beat this company. I got the info from the “legit street cars” YouTube and because a preferred customer. Not only to I save money but they give me all the information I need for my vehicles on the site but they deliver it to my door. I’ll never go back to another company

When I saw this, I had just read an article on upper valve deposits. Most EFI vehicles have this issue. Added a bottle at 1/2 tank and filled. The upper intake tapping at cold start has almost been eliminated, still have 1/2 tank left. Will probably run another tank of this, followed by tank with P.I. Engine is quieter, smoother running and have gained 1 mpg. Vehicle, 2015 Crosstrek with 97000 miles. It does seem to have made a difference.

Have Not had Any Adverse affects from using this product.

You'll really notice the engine getting quieter and the idle smoothing down after using this product. Peace of mind knowing that the valves and seats are getting a good clean and lubrication.

This stuff works! My truck has increased hp and mileage.

This thing works magic!

I use “top tier” fuel and figured I’d add a top tier fuel additive. I plan on following up with AMSOILs P.I. Performance enhancing fuel additive at every oil change just to keep things running well.

I have used this product In both my 1999 Lexus 300ES & 2003 Ford Explorer Sport for four tankfuls of gas. While I can't tell you if it lubricates the upper cylinders, I can tell you that it has improved the MPG in my Explorer by 1.5 MPG and in my Lexus by 2 MPG. Thanks AmsOil.

This is more like an update on this product. I've used this almost five years on a 2018 Ford Edge Duratec engine. Early results showed about a 3 tenths of a mile increase in gas mileage (This is my wife's car so no feathering on my part to get better mileage). Two other brands I had experimented with gained 2 tenths of a mile gain in mileage. The reason I started using this was to lessen wear and extend the engine's life. Can definitely recommend for a multipoint injection engine. I would hesitate to use for a direct injection engine. No unusual deposits on the tail pipes but it appears to have blackened a K & N air filter after 50 thousand mile so an oil catch can would be beneficial. The engine is in perfect condition along with the catalytic converter. I plan to to add an oil catch can soon.

Have used this Product in both my vehicles for years and have had no issues with fuel delivery, both run very smoothly as when they were new, A++ Product

SIMPLE THE BEST . INSURANCE INSURANCE

All products or lubricants are instantaneous, this 1 is not the exemption.

Use this top cylinder lube & feel how smooth the engine operates. It almost feels like the engines has just been tuned it runs so smoothly.

I recently purchased a 2005 pickup truck that ran a little rough. I decided to get a case of AMSOIL Upper Cylinder Lubricant Corrosion Inhibitor, hoping to see some improvement after a few tanksful. Well, the improvement was VERY noticeable before I used the first tankful. I'M A BELIEVER NOW!

Very reasonable cost for a little added protection for the most important part of my vehicle

Run this in your ride and your car will be happy.