I think it's just a guidance than some hard requirement of 4 oil changes. My car was burning a quart every 1K miles and it took just two VRP oil changes of 5K each and it seems to have completely stopped at 156K miles. I could probably switch to another oil at this point till I notice the oil level dropping again.
I'm still going to continue using it just because it worked so well though. Of course, it helps that I always did 5K oil changes since new so the engine was pretty clean and the only issue was stuck piston rings.
I'm still going to continue using it just because it worked so well though. Of course, it helps that I always did 5K oil changes since new so the engine was pretty clean and the only issue was stuck piston rings.