Why I switched from Pennzoil Ultra Platinum to AMSOIL Signature

Pennzoil’s flagship product, Ultra Platinum, is rarely in stores but maintains a good reputation. It’s also, since FCA moved from Exxon to Shell, the factory fill on SRT vehicles. And since the 6.4 Hemi in their heavy-duty trucks is actually a tweaked Hellcat motor, it’s also the factory fill for the trucks.

When FCA moved from Exxon to Shell, they also implemented a standard called MS-12633. It’s not a difficult standard to meet – but requires years in fleet vehicles to acquire. Some speculate – myself included – that they did this knowing that almost no one else (like Mobil) had the standard (yet). So it was an easy way to force people to use Shell products in FCA vehicles.

So why you can buy a myriad of 0W-40 synthetic oils, there are only two that meet MS-12633 as required by FCA in the 6.4L Hemi. Pennzoil Ultra Platinum and AMSOIL.

I wasn’t incredibly excited about this upon buying Yeti. I’ve never been a big Pennzoil fan. But like I said, Ultra Platinum has a great reputation and in pretty much every test knocks the socks off other quality oils like Mobil, Redline, Valvoline Syntech, Royal Purple, and others.

When I went to do the first oil change, I was even more disappointed that no one stocks 0W-40 Ultra Platinum locally. Another ploy to get you to the stealership I suppose? And on Amazon, it’s about $10 a quart. So the required oil by FCA has to be ordered and is as expensive as the most expensive motor oils out there.

I decided right there that I was going to use Blackstone to perform tests on every oil change. The owner’s manual calls what I do with the truck “severe service” and wants me to spend $70 on oil alone every 4,000 miles. I thought for sure by testing the oil, I could move to extended drain intervals using Pennzoil’s premier product and save myself some money and maintenance.

Imagine my horror when the first three oil changes (4,000 miles, 8,000 miles, and 7,000 miles) all showed break-down in the viscosity of the oil. I changed first at 4,000 as a “break-in”. Not required or recommended by FCA, but old habits die hard. And honestly, I’m glad it did. The contents of the oil were alarming.

The next was per the oil monitoring system and the manual – 8,000 miles. The results of which had me switch to 7,000 miles. With hardly an improvement.

After the second change, I had already decided that my fourth would be with AMSOIL. AMSOIL too has a fabulous reputation. Their severe service interval is 15,000 miles (vs 4,000) and it’s cheaper than Pennzoil. I felt like I had nothing to lose… it won’t perform any worse, right?

And AMSOIL didn’t disappoint. Viscosity stayed exactly where it should have with the highest flashpoint yet. And this interval was probably the hardest the truck has seen yet hauling our Four Wheel Camper around in the heat of summer in addition to it’s weekly hauling/towing regime.

I’ll be using AMSOIL going forward and continuing to send in samples as I work towards their 15k mile service interval. Hey, a guy can dream right? In the meantime, if anyone out there wants a screaming deal on about five quarts of Pennzoil Ultra Platinum – let me know :D