When I am done with my Auto Rx treatments I would like to use Mobil 1 every 3,000 miles.By the way I am using ARX with Chevron 10w30 dino and wix filter for 70 miles into first treatment.Digital dash mpg readout went from 20.8 to 23.3 in one day's 70 mile drive, lotta fun watching the gauge go up Anyway, after the treatments are done I need a good Mobil 1 for 3,000 miles. Manual "prefers 5w30" but my 1993 manual for my old car (totalled out) recommends 5w30 but says you can use 10w30 for warmer 0 to 100+ weather.My car has the 4.6 Liter V8 1995 engine with 133,000 miles on it. Drive it 3 to 4 times a week.Sometimes only once or twice.Some highway and stop and go with some big grocery loads. Down here by Austin,Tx it stays pretty warm (100 today ).Since it's not a daily driver I do get some cool starts (not freezing cold) would I get some benefit from the 5w30 or 0w30? Should I just use 10w30 with this engine and temp? Is 0w30 and 5w30 not good for a engine with 130,000 well kept miles? Would frequent oil analysis help decide the grade to go? Maybe I am just to careful? Thanks for your opinions! P.S. The SuperSyn Mobil 1 doesn't have esters ? It would work great with maintenance doses of ARX ,right ?