Here's an updated post on my friends pick-up. He hauls a 4,000lb trailer daily with this vehicle as part of his electrical supply sales business. I installed Amsoil SSO and an EAO filter for him (he'd been going to Oil Can Henry's every 4k miles prior for fills of Castrol GTX), but I wish I would have asked him about air filtration. Come to find out he was running a K&N rock catcher and the silicon is evident . No make-up oil was added during this interval. Needless to say he is sticking with the SSO and EAO combo following a severe service 17,500 mile PM schedule.