Who spends $50. for synthetic oil? Also Synthetic oil is not just for high performance engines and provides excellent protection for any engine beyond 1983 when seal tolerances were reduced to accommodate these oils. I would not suggest switching from a conventional to a synthetic oil on vehicles of any year beyond 50,000 miles since the seals have been conditioned for that type of oil at that point, but if it is a rebuild and all seals have been replaced a good synthetic oil will provide excellent protection to any engine and the stress load put on an engine in offroad situations most here place them under would be even more beneficial. My current rig was bought with over 200,000 miles on it and I run a high mileage blend due to that but would never go full synthetic unless I did a full rebuild.
