I have always used Valvoline royal blue with fleetguard filter every 5k. Not religiously so if it went over no big deal. I chose 5k simply because its an easy interval to remember and takes me about 6 months to get there. 2 oil changes a year. Swap the fuel filter with a new fleetguard every 10k. Extend the drain hose on the fuel filter housing to keep the draining process clean. Throw a fumoto valve on the oil pan.