Originally Posted by Lexusfreak
My problem is (as some of my other posts will verify) I can get a bit anal when it comes to the maintenance of my vehicles & I usually want to use the very best parts & fluids available......but because I am a fairly 'new' Subi owner......I'm worried that 'curiousity ***** the cat' in that I will do more harm than good. ;)
Dexron III is one of the best hydraulic fluids money can buy... the reason it is so cheap is that it's made in such high bulk.
Better brands of Dexron III are advantageous in some cases, because they have a different detergent additive package and respond to cavitation differently. I have typically used Castrol or Valvoline fluid, but any major brand will do. Avoid off-brand ATF for the transmission... in the power steering system it doesn't really matter.
Do NOT use "Max Life", "Extended Wear", or any other ATF designed for "high mileage transmissions". They have additional gums, sealants, conditioners, and etc that don't work well in a Subaru. Standard DexIII only.
If you're super-anal, Castrol makes a SYNTEC full synthetic Dexron III that meets the full DexIII spec but supposedly
has slightly better thermal characteristics and service life. I don't really buy that, but that's what they say in the marketing material.
Honestly though, the regular Dexron III is excellent and is what the transmission is designed to run. Synthetic is a waste of money IMHO and offers no real-world benefit over standard DexIII. Like I said before, Dexron III is one of the most overengineered fluids in the world... the only reason they offer a synthetic version is to get more money out of your pocket.