505 CRO Oil System Treatment - 12 oz Engine Oil Additive - Cleans Sludge, Reduces Emissions, Quiet Smooth Idle & Restores Performance in High-Mileage Gas & Diesel Engines

I have a 2016 Jeep Cherokee with 330,000 miles. After amazing results using ATF Chemical 505 CRF Fuel System Treatment (see separate review), I ordered this ATF Chemical 505 CRO Oil System Treatment. I believe my results are of particular interest because I did not perform the treatment by adding the product to dirty old oil, as you would right before an oil change, but I added the product to fresh clean oil right after an oil and filter change. Wait till you see what happened. The instructions say to add the product to your engine's oil, run the engine at "high idle" (some mechanics say @ 2,000 RPM) for 10 minutes or more, then drain the treated oil, remove the oil filter and install a new filter and new oil. However, what I did was last night I added the product to the fresh oil that was in my car, ran the engine at regular idle speed (say 750 RPM) for 10 minutes, turned off the engine and let it sit overnight. This morning I started the engine and moderately drove the car (2,000 RPM max) for 40 minutes, parked the car and let it sit for a few hours, then drained the oil. I was very curious to see what the oil looked like when I drained it. Would it look like the brand new oil that I had just put in the car? The answer is an emphatic NO - the oil was PITCH BLACK - it looked like old oil coming from an engine that was overdue for an oil change. In my opinion this stuff does what it was designed to do. It cleaned out the built-up carbon deposits internal of my engine. After installing a new filter and new oil I drove the car today as normal for about 90 minutes around town and highway. It is probably too soon to tell but I think the engine runs smoother and quieter. I will now be using these products on all my vehicles (5 cars/trucks, 4 motorcycles) and recommending this product to everyone. I am SO glad I found out about these products from a mechanic on YouTube who says these are "products your mechanic does not want you to know about" and that they will "make your vehicle last 3x longer". I have no doubt this is so. Easy to use. Does as advertised. Worth every penny.

It's worth the $55. I have a Toyota sedan that is 15 years new at 160,000 miles, as a maintenance action I treated the fuel tank with one bottle of 505 CRF Fuel treatment and while parked, ran the RPMs to 3,000 and held it there for 2 minutes to burn off carbon and clean the injectors. Within half a minute or so I could actually HEAR the car running to smoother. It reminded me of tuning an out of tune guitar string, the pitch/tone of the engine changed and the whole engine sounded smoother. 6 months later, the car still starts and runs like a dream. I can't promise you the same results, but I wanted to share my results with this product. As a sidenote...if you are reading this and have a car over 120,000 dont sleep on installing new spark plugs and install a new PCV valve. On some cars the install is relatively easy and the part is only $8 and now my car no longer burns oil! no more 1qt per month burned...

I haven’t used it yet, but the product comes with very high recommendations

Used product twice so far. Noticed a little increase in mpg. Plus what I am unable to see. Scotty Kilmer spoke highly of it and I trust he’s opinion. Yes it’s pricy item but I think it’s worth it. I use it twice a year.

It improves the engine life, and clean all residue of sticky oil and dirt.