Customer Ratings & Reviews

Product is great, however shipping was twice the cost of product. So will purchase at local store for what I need. Will not order on-line.

Great stuff keeps my Honda working like a charm

I started using this two years ago when we bought a new car for my wife. I also started using it on my Gen 3 Tacoma, which is supposed to get 22 mpg combined miles, but like most mileage estimates that was with a small child driving and no back seat. I now easily average 24+ mpg and have gotten as much as 26.5 mpg, with the only change being using the Upper Cylinder Lubricant with every fill up. This mpg increase also correlates with less wear and a cleaner fuel system.

I have a 2020 Ram 1500 hemi etorque, not only did this absolutely get rid of the dreaded Ram tick it actually is smoother than it was when I drove it off the car lot! I will always use amsoil products in everything I own. It’s simple, it does exactly what it says it will do just better! It also eases the stress and worry when you use a product that is actually good for your vehicle!

If you drive a newer vehicle with Direct Port injection you must try this product! It keeps the engine running smoothly and keeps the upper cylinders clean!

seem to do a very great job

This is a great product, and helps with gas mileage and a better running engine

Keeps my fuel system and injectors clean.

I Run Premium fuel in my 2022 RAM 1500 the upper cylinder lubricate you are supposed to use it in every tank. I do believe that it works as it should use it every second tank fill. The long neck really helps with the capless fuel cap. I would recommend this.

I use it once a month to give my engine extra protection. I have 150,000 km on it and my engine stays as quiet as a brand new car.

run this every second fill up engine runs amazing , smooth, and better fuel economy

I purchased three products from AMSOIL, The Upper Cylinder Lubricant Corrosion Inhibitor, The DOMINATOR® Octane Boost, and The P.i.® Performance Improver Gasoline Additive I added all three to a full tank but, prior to doing this, I had filled the tank with Top Tier Fuel for this test Shortly after I took a ride, at first, I noticed nothing, but the very next day I put twenty miles on her, and that is when I noticed she ran quieter, and that the pick-up was back I highly recommend this product for older vehicles, and I want you to know, that these products are not a gimmick Check it out for yourself

Increase MPG when added. I usually add in once per month, but it seems to have a positive effect on MPG for at least 2 or 3 tanks. I put in all 3 of my vehicles.

Helped with idle along with PI additive

Keeps my vehicle running great

If you do a little research into Cafe standards and what is missing in fuel you will want to use this. Not all fuel has the amount of needed additives for today's direct injection engines, you want to keep those injectors clean and the rest of the upper cylinder too. I have a 2.4 cylinder turbo boxer engine 2025 Subaru, it really needs this. In practice terms I see a bit more pep in my step with this but not as much as with Amsoil P.I. I think every task is too much but every other tank should be just fine as I only allow a tank to go to 1/4 full and then refill. The bottle handles more than my tank holds so should be good to go.

Helps quiet the noisy GM lifters. Helps smooth out the ride. Just as good as the in-store 30 buck cleaners.

This product is added at every fill up. I also use the AMSOIL P.i.® Performance Improver Gasoline Additive at the recommended intervals. After a short time you will notice a huge improvement in performance! If your engine uses direct fuel injection, which can cause a Carbon buildup, you have to try it!

I use this at every oil change. Does the job.

This product used with every tank of top tier gasoline combined with PI Performance (every oil change) makes me confident my 23 4runner will always be in tip top condition.