Since I built my Monster Miata I have been using Power Steering fluid in the PS pump. I am using the old style Ford pump (from about a 76 Mustang.) and the Miata steering rack. I just noticed that the dipstick on the pump calls for Automatic Transmission Fluid. Assuming that the pump wants ATF and the rack probably wants Power Steering fluid, which should I use and why?
tuna55
SuperDork
7/11/11 11:28 a.m.
What I have always heard (which means, I don't really know):
It doesn't matter. It doesn't get used that much in most applications and it's pretty much just hydraulic fluid. I've always used type F because it was cheaper. All it does is carry pressure from one place to another. If it has lubricity and doesn't kill the seals, it should be fine.
Unless specifically called out in the manual, pump literature, dipstick, or service information, I have used ATF in PS systems. I believe PS fluid is just dye-free ATF.
Like my wife's Avalanche, I only use the recommended PS fluid in it because of the Hydro Boost system on it. Same with the hydraulic fan setups on the old WJ's.
My Nissan and Toyota both say use Dexron II ATF for the power steering.
Honda on the other hand says only use Honda spec power streering fluid, as well as Honda brake fluid and Honda antifreeze.
i use whats cheaper.. normally ATF since I always have it laying around...
lol sadly untill a year ago I had no idea there was a difference... I use what the manual calls for now lol... prior i'd always used PS fluid due to basic logic of "its for power steering" lol