[Eldorado]

ethanol has a neutral pH rating... pure water is more acidic than ethanol.. but it is somewhat corrosive to *some* rubbers.. however, any cars made within the last 15-20 years should be alright and free of those rubbers. ethanol also usually only negatively affects cars with carbs.

that said.. the owners manual said it's cool... and there's obviously a tollerance built into that.. so using 10% eth in your gas shouldn't do a stitch of damage.