I have a small leak on my power steering, which I've been topping up with power steering fluid. I've since found out it needs to be automatic transmission fluid, i presume Dexron 3.

To replace the power steering fluid with ATF do i need to drain all the power steering fluid out and flush it, or can i just get most of it out and top it up with ATF?

Hi Simon,

ATF and PAS fluids are similar but not quite identical. ATF contains detergents and friction modifying agents, that PAS fluid does not. If you have topped up your PAS with PAS fluid, then that is fine mate. Don't bother draining the system, and don't put ATF in your PAS! The friction modifying agents in ATF are heat-resistant in nature, to enhance friction between components in the clutch pack for better grip. On the contrary, the PS fluid is mainly for lubrication and reducing friction between various parts in the power steering system.

I have only ever used PAS fluid in my PAS - I had a major leak when my PAS fluid cooler rusted through some years back - it's still all in there and still all working fine ? 

Thanks Richard. I think I'll drain the PAS at the weekend and fill with new PAS fluid, my cars been off the road 10 years.

I thought origionally it was a leaking hose, but actually turned out to be the nut leaking that connects the hose to the rack.

Thanks again.

Seems the Dexron III ATF & PAS fluids are pretty much universal for both purposes, according to Opie Oils....

Nissan Fairlady Z Petrol Coupe 3.0 Twin Turbo Power Steering Fluid (opieoils.co.uk)

 

 

By the FSM:

re ATF vs PS fluid:

http://www.twinturbo.net/nissan/300zx/forums/main/view/1109051/Power-steering-problems-and-solutions.html

Edited June 30, 20223 yr by AndrewG