This is my first post and second oil analysis. As you can see, the vehicle has 186,142 miles and 4,353 miles on the oil. It is the original engine and sees mostly highway mileage. I use a standard (not synthetic glass) oversize Baldwin B2 filter. I used to change the oil around 3,000 miles. After having it analyzed, Blackstone recommended trying 4,000. This sample was over 4,300 and they recommended going even longer! Pretty good for dino. Comments welcome...