I’ve been running Quaker State Defy High Mileage in an older car with good results controlling oil seal leaks. The PQIA just released some results which were covered in a post last week. The Defy product used to advertised on the front of the bottle as having a higher level of zinc. Now the Defy brand name only shows up on the back of the bottle and while it does talk about zinc, according to tests done by the PQIA in 2014 and 2018, the zinc level has gone from 1071 ppm to 890 ppm. Anyone know the full story on why Quaker State has made that move? It’s like it’s now more in line with the other High Mileage oils.
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