So when I first bought my ap1 I used mobile one and I changed to gtx castrol highmilage..... Is it ok to switch back to full synthetic after running that type of oil???? The highmilage is a blend btw... Is the switching thing just a myth????

 

I used M1 for 100k, switched to GTX high mileage for 60k to cut down on consumption. IIRC GTX is not a blend. but, yea It's ok

 

From what I can tell (i.e. quick Googling without exhaustive verification) it's outdated info. Modern synthetics supposedly contain additives for proper seal swell.

 

You are correct, it would be no problem to switch to a modern synthetic oil. I do recommend just sticking with synthetic .

 

No prob switching back.As stated,stay with all syn..it's just better.

Oil is cheap...hardparts are not.

\rlr
Carolina