Originally Posted By: crazycrak
I recently switched from Pennzoil Platnum 5w-30 to Mobil 1 EP 5w-30 and I was wondering which oil is better and how do their additive packs stand up to each other
You cannot really compare the add packs since their base stocks are quite a bit different. PP is basically a Group III oil, with some small amounts of Group IV. M1 EP has substantial amounts of Group IV in its base stock (probably 30-50%) so it doesn't need the same additives that Group III needs.
Either oil will work fine in the applications they are suited for, but since M1 EP is specifically formulated for extended drain intervals, it should last longer than PP or regular M1.