oil recommendations

Leaking in older engines happens, but it's a way overstated problem. If an engine has been fed dino oil for a long time, and has not received changes often enough, a layer of varnish, sludge, or both may form over critical seals. Those seals, now deprived of contact with fresh oil and its seal-preserving additives, begin to dry out and shrink slightly. Then, if you add syn oil, its superior ability to clean and suspend grunge (I'm overgeneralizing here, some syns are better than others in this regard), the layer of varnish/sludge is cleaned away and the oil hits the compromised seals and can leak until the seals are reconditioned. If an engine is fed syn its whole life, this mechanism never has a chance to come into play.

Mobil-1 (not "Mobile" by the way, that's a city in Alabama... ) is fine stuff. I ran a Honda Civic hard for ten (10) years on the stuff, and when I sold it with over 150k on the odo, the inside was spotless and silvery without even a trace of the yellowish varnish you often see in well kept engines fed dino oils. There are, however, plenty of other good choices on the market.