If you ever want to see what accumulates in the bottom of your engine, try changing your old oil into a white refrigerator vegetable crisper pan. Oil changing was never much of a priority for my daughter and just seeing the difference a couple thousand more miles made in accumulated sludge in her engine oil and my engine oil has me changing more often to get rid of the dirt. I've got an extra $20.00 or so lying around for new oil with filter and the time to change it, so the peace of mind of having cleaner oil has always been worth it to me.
