Maybe you have not explained it clearly to the salesman? In my experience they sometimes need it explained in little words. The ones that do not listen anyway. I am good with ones that listen and respect others.
It was explained in very clear language further back.
and in a PM...
all that aside, the cost of having an 'oil analysis' done negates the "savings of using any synthetic oil".
the oil needs to be changed out at regular intervals to negate the effects of combustion and water condensation products.
I'm not against synthetic oils, I have it in the F-150 and in a '07 Pontiac Vibe... both because I was told to do it that way or else.... and SWMBO'd gets the last laugh...
The F-150 has been on syn oil for 229,000 miles, so who am I to say no to that?
The Vibe has been on syn oil since it was new and the title is in SWMBO's name....
neither vehicle seems to use any oil between changes, so I'm not knocking "success" as it were.
Oil discussions are fun, and we all have a chance to learn a lot.
I have two threads to another forum that documents the effects of many different types of oils... and in the end, that user could not make a claim that synthetic is "god's saving grace" for the oil to use.
Here is his 1st thread and the start of his documentary:
Here is his 2nd thread and the end of the documentary and his conclusions.
and here is an explanation of the different Viscosity ranges.