2021 test2 productsEngine Oil & Fluids

Which Motor Oil Brand Wins?

We compared 2 motor oil options head to head. Pennzoil Platinum Full Synthetic came out on top. See the measured results, the runner-up, the budget pick, and a link to the full test video.

The verdict
Winner

Pennzoil Platinum Full Synthetic

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Runner-up

Honda Marine

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The measured results

Every number below is read straight from the test. Scroll sideways to see all measurements. Products are listed in the order they finished.

ProductEvaporative loss (410F for 2 hours)Foam/anti-foaming test (5 minutes)Corrosion test, 2-minute checkCorrosion test, 24-hour final result (rusting agent applied 3 times)Lubricity/film strength testCold oil flow race (new and cooked samples, minus 40F)Oil analysis, molyOil analysis, boronOil analysis, calciumOil analysis, magnesiumOil analysis, phosphorusOil analysis, zincOil analysis, flash pointOil analysis, TBN
1Pennzoil Platinum Full Synthetic 10W-30started at 410.9 g, ended at 407 g, a loss of only 3.9 g, described as a huge win over Honda Marinecleared up much faster and more completely than the Honda Marine oilappeared to have slightly more oxidation than Honda Marine at this early checkboth oils did very well, but Pennzoil showed a bit more rust, especially in size and intensity, compared to Honda Marinelost narrowly to Honda Marine, which had about a 3 percent smaller wear scar; described as the closest race between two brands the presenter had seen in a long timewon the overall race; the cooked Pennzoil sample staged a comeback to cross the finish line slightly ahead of Honda Marine71 parts per million209 parts per million863 parts per million613 parts per million557 parts per million619 parts per million460F, better than Honda Marine's 400F6.5, slightly higher than Honda Marine's 5.9
2Honda Marine SAE 10W-30 (Honda Genuine Oil, meets NMMA FC-W)started at 404.64 g, ended at 385.86 g, a loss of 18.78 g, far worse than Pennzoilhad noticeably more air bubbles remaining and cleared more slowly than Pennzoil, despite manufacturer claims of a superior anti-foaming packageappeared to have less oxidation than Pennzoil at this early checkboth oils did very well, but Honda Marine showed less rust in size and intensity than Pennzoilwon narrowly with about a 3 percent smaller wear scar than Pennzoilcompetitive throughout but ultimately lost; the cooked Pennzoil sample edged it out at the finish37 parts per million2 parts per million1,819 parts per million, more than double Pennzoil's11 parts per million1,039 parts per million, nearly double Pennzoil's1,203 parts per million, nearly double Pennzoil's400F, lower than Pennzoil's 460F5.9, slightly lower than Pennzoil's 6.5

How it was tested

  • NOACK-style evaporative loss test at 410F for 2 hours
  • anti-foaming test using a shaken quart jar setup
  • corrosion resistance test using a hydrogen peroxide, vinegar, and salt mix, checked at 2 minutes and again at 24 hours
  • lubricity/film strength wear-scar test
  • cold oil flow race at minus 40F, new and heat-cooked samples of both oils
  • independent oil lab analysis (moly, boron, calcium, magnesium, phosphorus, zinc, flash point, TBN)

In my opinion, stick with the oil that's designed for a car. Unfortunately, the marine oil just did not perform very well compared to the oil that's designed for a car.

From the test video verdict.

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