Every 4500 miles and the key word is "I" change the oil. I don't trust the idiots at wal mart or jiffy lube to do it for $6 an hour. I like to do my own becuase when I'm underneath the car i know what is going on with it. I don't all the sudden realize that an axle seal is leaking or a u joint going out. I religiously used Mobil 1 Clean 5K and a Fram extreme guard filter. Truck has almost 240,000 on it and runs like a top.
Old truck I did every 3k and used the regular fram/ Pennz and it made it almost 300,000 before the motor went.