I've had this run of M1 0w40 in my truck (8.3L V10, Viper engine) for 3,141 miles and just over one year (stored during winter months). I run the Mopar "Viper" specific oil filter, K&N air filter, and the truck has some mods (headers, exhaust, tune, colder thermostat, etc). This is the OEM spec oil/grade, although I'm sure the formulation has changed in the past 15 years.