You raise a good question. I change when the message appears. My truck is not deleted. I've read other posters who also state if your truck is not deleted, change when the message appears. Some may get close to the 7500 mile mark, but IMO, they are deleted or not much grocery getting with them, lots of highway driving, or towing.Sorry to hijack, but do you guys change the oil when the light comes on, or do you follow the owners manual recommendations?