i have an 09 taurus and the manual says to use mercon v as the atf for the transmission fluid but also for the power steering fluid. i was wondering the same thing. do i have to use mercon v in it? in my camry, the atf and ps are totally different though the ps is an atf, but just gm atf, as it takes dexron for the power steering and type4 toyota for its atf, and i'll use maxlife for the toyota camry's atf and ps this time since maxlife atf is ok for toyota type 4 and it's dex/merc, but what about using maxlife in the ford? it says it's mercon lv but not a mercon v, so i don't think i'll use maxlife atf in the tranny on the ford, but was thinking about using it as the power steering fluid. is that ok, or should i use mercon v? what about prestone power steering fluid? i heard from a guy at autozone that power steering fluid is better for the seals than using an atf as the power steering fluid. is this true, and should I use power steering fluid or was the guy tricking me and trying to sell me the prestone? why would they make "power steering fluid" esp by prestone which is ubiquitous if most cars use automatic tranny fluid? there has to be some merit in using it otherwise it woulnd't exist. could i use that in either the taurus or the camry?
i'm especially curious about use of valvoline maxlife atf (says mercon lv, not v) for the power steering in the taurus, and mercon v is backwards compatible with mercon but that's not the case with the lv, so lv is not compatible with mercon v systems, right?
and could you use dexron in the taurus power steering or atf_4? would that be better or worse? my mechanic recommended spark plugs and power steering fluid but i think the PS is still good and it's red, so why is he telling me to change it? he's trying to sell me a service I don't need? and the car has 90k, isn't it true i can wait till 100k to change the spark plugs? thanks.
and does lubegard red wear off, as in do you add it every year, or would that be overkill and you'd "overdose" on it, or should you add it every year since it will break down and wear off? thanks.