Hi... Since I'm starting college soon, and probably not working in the 1st year, my '97 4.6 mod T-bird is going to be driven very little(I WILL drive it on interstate at least once a week to keep it in shape), and I've decided to go to 6-month OCI's, one for winter, and one for summer. ( I haven't seen GC in AZ close to me in NC yet, but I have to check in Raleigh, if I find GC, I would run it year round, and change every 6 months)) Now for winter(at least 5-6 months), I've decided on dealer oil(MC): (A) would Motorcraft 5/20 or 5/30 be better? or is the difference not big at all? [Why I'm undecided about MC 5/20: I know what a good oil the MC 5/20 is, BUT I still haven't seen a great UOA on a mod. 4.6 built previous to 2000, which could have different bearing composition from a mod. post 2000 which have been the ones with the good 5/20 UOA's(noone has been able to find out anything about this difference in bearings yet, as far as I know: 1996-97 mod bearing composition is still a mystery!!!./ all my research to find if 97 mods and post 2000 mods have the same bearings were in vain). AND, those good UOA's mainly came from mod.engines with relatively low miles; mine has 98k miles now. Otherwise I'd put MC 5/20 without any hesitation] (B)or do you guys think that the stability of 5/20 compared to 5/30 weighs more than factor that my engine has high miles.? (C) In general, do these MC oils have the capability to handle 5-6 months of short-trips, including winter months (in NC)? (D) IF I don't find GC in NC, would MC 10/30 be good enough for 6 SUMMER months(short trips)? (currently I have M-1 5/40 in, will dump it when it starts getting cold) would appreciate any help with this decision.... Thanks a lot.