Gearbox work

[Bri963]

One argument against this (good) point is that contamination occurs at the same rate regardless of the type of oil.
Fresh oil is clean oil, so you are not only replacing degraded oil, but removing contaminates at the same time. This doesn't hold true for all applications, but is worth considering.

I get what you’re saying, but contamination is mainly from wear, after the initial running in period. So the better the oil, the less wear, and contamination. Also, with synthetics you don’t get the added contamination from oil degradation residue.

 

[Gecko]

Fair point, but in a dusty environment, it'll get in through the breathers.
Synthetics certainly cope better with moisture.

It is however worth recognizing that there are many types of "synthetic oil" and they are not all created equal.

Understanding Types of Lubricants: Synthetic Oils

Sometimes when we think of synthetic, it tends to be in direct opposition to natural: synthetic fibers versus natural fibers (polyester vs cotton), synthetic or artificial...

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