Mobil 1 15W-50 Synthetic (SM) with ZDDPlus additive in the Road Runner; Rotella T 15W40 with ZDDPlus additive in the Barracuda; can't have too much zinc and phosphorous in either one...

Glenn
67 Barracuda Convertible (PP1)
68 Road Runner (LL1, 69,000 Original Miles)