31520 HPS 5W-20 High Performance Street Synthetic Motor Oil with Synerlec - 1 Quart Bottle

I use it in my 1973 Ford f250 360CI. Runs noticeably quieter and very smooth compared to your average conventional oil. I would say this is great stuff for older engines with flat-tappets. I messaged Royal Purple and asked what they recommended for an older car and this is the stuff. Lots of Zinc and Phosphorous/ZDDP substitute for the older technology. It also has an extremely high viscosity index, out of any oil I've seen, so you know it will perform great in those temp extremes as well, hot and cold. At about 11 bucks a quart if you buy in bulk, it's also hard to beat the price when comparing to Amsoil or Redline, although those would be great choices as well. Comparing other options, Amsoil is a bit thinner than this and offers a little bit better cold weather performance and longevity, but is pretty expensive. Redline is nice because you know what they put in it, no secrets with them--very high quality group 5 ingredients. It's also the most robust, and probably offers the greatest protection in extreme operation. Don't necessarily know what they put in the HPS, though I imagine it's a high quality group 4/5 ester/PAO base, either that or its got a pretty beastly additive package to perform the way it does. Mobil is another obvious option and is probably the best all-rounder for your newer cars, though some of these "boutique" oils I've mentioned offer more specific things if you need them. Overall, I think this one wins the comparison for price and if you don't change the oil every 20,000 miles. Personally, I wouldn't wait that long on any vehicle. Maybe 10,000 at the most in an engine that is perfectly sound.

Perfect for my 2013 Cadillac CTS-V. Been using this oil since I've owned the car with 6,900 miles on it. Oil analysis always comes back great.

This Royal Purple oil is straight fire! Has a premium feel, great protection, and it works like a champ under load. I used it in my Mustang and it smooths out the engine, quiets the noise, and holds up strong even in heat. No sludge or breakdown. If you want a smarter oil that works as hard as your ride, this is it. No oil leaks, and is fully synthetic. No burning smell. It’s not cheap but worth the money for sure!

High quality high performance motor oil. Good for himies and lot of large engines excellent quality.

Well packed and quick delivery considering where I shipped it to { Nowhere Montana ;-) }. Exactly what we were looking for and nobody carries it locally. A quality product from a reputable company. Worth every penny for just a bit more engine protection on a hard working pickup truck.

High performance oil. The name says it all. I know it is not under warranty for any dealership. But let me tell you. This is the good stuff. Period. I been using for two years now that I'm running AutoX.

Best oil on the market it’s very comparable to what my vehicle calls for and then some great value for the money I get even better gas mileage when I use it royal purple let’s go. I wouldn’t have any other way.

Excellent synthetic oil! Use it in my 140 Suzuki four stroke outboard. Oil was delivered on time as indicated.

Ottimo olio che mantiene la temperatura motore costante e inferiore rispetto ad altri olii motore

A bit painful customer experience, however, the oil is a good product.

Perfetto per motori diesel preparati 😎

エンジン音が静かになりました

粘度が高くてもサラサラしていてフリクションロスが少ない様に感じます。