Update:
'92 Aerostar 3.0 V6, 118,000 miles: 5 quarts Maxlife Synthetic SL 10w30 with Wix 51515 filter (oversized).
'97 Itasca Sunrise motorhome with Ford 7.5L V8, 48,000 miles: 6 quarts Maxlife SL 10w30 and 3 oz of 21000 ppm zinc PCMO additive.
'95 F150 4.9L 138,000 miles: 6 quarts Valvoline Durablend SL 10w40 with 10 oz of the PCMO additive, is running about 2000 ppm zinc in the crankcase at 5000 miles on the oil (UOA on site) and currently at 7000 miles, shooting for 9000 plus miles.
'92 Aerostar 3.0 V6, 118,000 miles: 5 quarts Maxlife Synthetic SL 10w30 with Wix 51515 filter (oversized).
'97 Itasca Sunrise motorhome with Ford 7.5L V8, 48,000 miles: 6 quarts Maxlife SL 10w30 and 3 oz of 21000 ppm zinc PCMO additive.
'95 F150 4.9L 138,000 miles: 6 quarts Valvoline Durablend SL 10w40 with 10 oz of the PCMO additive, is running about 2000 ppm zinc in the crankcase at 5000 miles on the oil (UOA on site) and currently at 7000 miles, shooting for 9000 plus miles.