I really believe in this stuff. I use it in my cars, snow blower and mower. I got over 300K on my last two cars and the engines still had great compression and burned only a bit of oil. My protocol has been to start with motor silk for the first oil change and then after that use this with each oil change. I use the fuel catalyst as well two or three times a year mixed in with Lucas injector cleaner.

As with many oil additives, its difficult to know just how well many of these products perform. I can only speak to what I've observed. I use this in all my vehicles, but I'm primarily speaking about my 83 Volvo 242 that I drive 134 miles/day round trip to work. The car had ~300,000 miles on it when I started using it, there is ~400,000 miles on it now. It has its Volvo B23F in place with a Volvo performance camshaft (H cam), a Stahl header and free flowing exhaust.

1. After about 10,000 miles (two oil changes), I saw a modest increase in oil pressure at idle. My presumption is that this was due to the cleaning action that this product exhibits and is allowing the oil relief valve to fully reseat. With another 90,000 miles on the ODO, this has remained the case.
2. The engine interior is much cleaner than it has any right to be with this many miles. I saw this when I had to replace the oil pump o-ring seal (common problem with these motors and unrelated to this product). There is some discoloration that is common on these motors, but the sludge that I was expecting in places was completely absent. I performed this maintenance after about 60,000 miles using the product.
3. Gas mileage is unaffected by this product alone. See #6 below.
4. Cranking compression actually rose between 10 & 20 psi (cylinder to cylinder) after about 10,000 miles and has remained at that level ever since. I test the cranking compression every 10,000 miles.
5. I actually use about twice the recommended amount per oil change. I pour the product directly into the new oil filter.
6. For the last 10,000 miles, I have also been using a product called LubroMoly. Prior to using Archoil, I just used the LubroMoly, primarily for cranking protection during cold starts. The combination of the two seems to have unexpectedly resulted in a mileage increase of ~1 - 1.5mpg depending upon driving style that day. The overall average is up a little bit since I started using the combination. The car averages between 24 and 26 MPG with winter on the low end and summer on the upper end.

Your results may vary. I would recommend this product to anyone wishing to maintain performance levels in their engines and keep them clean inside.

I use this product in a factory five Cobra that has seen some very harsh conditions on the track. The engine tends to run cooler and much quieter. The lifters now tend not to go flat at higher RPM!! I would highly recommend this seller for the product and also the product itself.

works great, releaved my injector issue after 2 oil changes. 6.0l

I don't know what it is about this stuff, but it just works. If you have rough starts in a PowerStroke 6.0, pouring 16 oz of this into the oil will fix you up in no time. Definitely makes mine happier and run smoother.