1990 Toyota Cressida - synthetic vs standard oil

I used standard oil (Pennzoil 10x30) for most of my over 390k Toyota Cressida 1990. The last 3 or 4 oil change I use synthetic Mobil 1. But now for financial reason I like to go back to Standard oil…What do you suggest?

If you are doing your own oil changes and your car does not consume much oil between changes, I would stick with synthetic but change to a lower cost brand.
But switching back to conventional oil would probably be fine.

You can switch back and forth between the two without harm.


I agree with old_mopar_guy. Switching back won’t hurt anything.

I actually used to love the Cressida… It was a Toyota Supra in business clothing. They were nice vehicles.

I agree with the others…just switch back to whatever oil you wish to use.