- Jan 19, 2017
- If you have to ask, don’t ask…
Admittedly, I had never heard of this concept until a few years ago. And I can’t seem to find much on it except that it is a possibility. I thought part of the API standards was a requirement for compatibility with other oils of the same rating, as well as backwards compatibility? Both of my vehicles get a variety. The Ford is a lease that I use for work, so it gets whatever the quick lube I take it to uses. Which changes frequently. And the Toyota gets whatever oil is on sale at the time or if I’m too busy to do it myself whatever the quick lube or dealership uses. The Toyota 2.5L engine requires 4.8 quarts but I only fill it up to 4.5 quarts or so. The remains make it into a 5 qt leftovers jug and will eventually go into the engine. This brew is a variety of 3 or 4 brands of both SP and SN + ratings. So is additive clash a real thing I should take into consideration here or is it a theoretical idea? Are there any published test or papers showing this has happened, what the consequences are or what mixtures should be avoided?