Originally Posted By: crazyoildude
Just curious what oil is considered to be the best at cleaning up a dirty engine and also protects against wear. I know Pennzoil Platinum was always a great choice but things change fast around here is that oil still a good choice?
The honest answer is that nobody here really knows what oil offers either the best cleaning or the best wear protection.
Any API SJ/SL/SM/SN oil will do a reasonable job of both, although we all have our favorites.
There is at least some reason to believe that wear protection and cleaning are antithetical, but the best cleaning oil probably produces no measurable increment in engine wear over the oil offering the best wear protection, which in turn probably offers no measurable loss of cleaning ability relative to the best cleaning oil. Whatever differences there are would be very small.
Amsoil's premium oils do look to have unusually stout add packs as compared to any OTS oil, for what that's worth.
Engines don't typically have much in the way of excess wear or deposits unless they're operated in such a way that they never get fully wamred up or they're run for OCIs too long for either the oil used or the operating conditions.
If I had an engine that appeared to be heavily loaded with deposits, I'd consider using a solvent in the oil, like Kreen or Berryman's.
OTOH, regular changes with any oil will slowly remove any excess deposits, assuming that the engine is operated in a manner that allows it to spend most of its time at normal operating temperatures.
If an engine is loaded with deposits to the extent that its survival is in doubt, any short term increase in wear involved in cleaning it up would be of little concern.