Regardless of gas or diesel I have always believed that oil changes are a quick easy an inexpensive to make sure the old guy or gal stays on the road. I always run Castro full sin and name brand filters. I have cars that I only change once a year as they don't reach the min milage requirement for a change. Plus it's always good to take a look underneath for anything amiss. I dispose of the waste properly. When like in the case of my Cat MH oil is in gallons not quarts I save a great deal over dealer service.
Thanks all