Originally Posted By: wemay
Originally Posted By: Clevy
...I'll pay the extra few bucks a tank for premium. Easier on fuel means less fuel burned which equals extended oil change intervals.
Winning
Hi Clevy, could you expound on this?
I will. Let's take a look at commercial trucks. Cat engines or example. In the lubrication manual for Cat engines, if the engine is getting less than 6 mpg (I know this sounds low, but we are talking about heavy semi truck engines here), the oil change interval is recommended at 15,000 miles. If the engine is getting over 6 mpg, it is recommended at 25,000 miles. This is for the Cat C-15. The oil is not being subjected to as many particulates, combustion acids, etc and possible fuel dilution issues when getting above a certain mpg threshold. Hence, the OEM recommends extending the drain if the fuel economy is above their determined threshold. Detroit Diesel, International, etc all have similar directives.
The auto/pickup OEM's don't elaborate on such details. Most folks either would find a way to mess it up, or ignore it altogether. But, they have factored it into may Oil Life Monitor algorithms. That is one reason the Oil Life Monitors are not all that bad when it comes to oil life.