Been reading some old posts on Series 2K 0W-30. Since it hit the market I have been using this oil in my 96 Cherokee for full time rural mail delivery. I am happy with the 2 UOAs I have done so far, but after reading several opinions on the old posts I have to question, would I be better off with a different oil? The Jeep now has 232,000 miles, about 80% actual mail route miles, and is using about a quart per 6000 miles. Last oil change I installed my old Amsoil dual bypass on it. My plan is to change the full flow filter and send in a sample for UOA at 12,500 miles, then as long as the UOA is OK, run it for another 12,500 and then change oil and filters. This would be about a 1 year OCI, vs the almost 3 changes per year I have been doing. The series 2K 0W-30 is advertized as "severe service" oil, and I consider my use severe. About 20 miles of gravel roads on my 90 mile route (430 boxes) 5 days a week all year long. Cold in the winter (well, most winters) and and hot in the summer. Also, I pull a 16 foot tandem axle trailer with it once in a while. So what are your thoughts? Is the costly Series 2K 0W-30 still the best oil for this vehicle? Thanks.