Impossible to review engine oil without some kind of lab analysis but the engine is still running so... 5 stars?

This is an awesome racing oil. I have a 2006 6.0 GTO and with this oil I believe it has gained at least 25 HP. Smooth and so much quicker than with the standard synthetic brands. I was really surprised by the difference. This is all I will run from now on.

I have been using Z-Rod motor oil for around 10 years in my street rods, both engines have been running silky smooth with no harsh noise conditions. I have never had any overheat problems or power stress incidents. Highly recommend this blend in your tappet valve engine.

Will order again

I have used this oil for several years and my engine is in perfect shape. 700 HP drag racing engine.

I've ran this oil in two race cars over the last decade and nothing else competes in my opinion.

Best in asphalt racing

Great service and great product! Will continue to order from AMSOIL.

Tried this in my 2018 RAM 1500 with a 5.7 because of the oiling problem with the cam. It has extra zinc and phosphorus which helps with wear and tear. With the first start I noticed immediately the engine run much quieter and smoother! Oil pressure was a few pounds higher as well!! I've only had it in my truck for around 1000 miles and am planning on sending an oil sample to see about the longevity but I'm betting this oil will be hard to wear out! Thanks Amsoil!

Great oil, but would like to see the line expanded to include single 40w, 50w or 60w.

The site was easy to navigate and product information spot on

I use Z rod oil as my brake in oil in my flat tappet cam motors. It never let me down. After brake in I use Domintor racing oil to handle the racing duty.

great for my vw aircooled. i am a premium member but, at 100 dollars for free shipping, i shy away. if it was 50 like it was one time only, ild order each month.

I use this oil in my pro charged Ford Mustang

When you need a little extra out of your crate motor and the best protection

Use this oil in my cammed 2012 camaro SS and I wouldn’t use anything else. Best oil hands down

I would recommend olive oil in your spaghetti. Enough said

Works great with gen lll hemi's too!

Always on time fast order and delivery alwa. Definitely recommend any amsoil brand of oil

Great oil and fast shipping It the only way I will ever buy my oil from now on