Posted: May 23 2007 at 14:12 | IP Logged

Hi All,

I have a 1984, 42’ Double Cabin.  Can anyone tell me what kind of fluid I should use in the hydraulic steering system?  Apparently there are systems that use ATF and those that use something like 0-30W oil.  I am away from my boat at this time so I can’t look in the autopilot manual.

David

Posted: May 24 2007 at 10:51 | IP Logged

3 of my 4 boats all took ATF - including my current Uniflite.  My Tollycraft demanded hydraulic oil.

Posted: May 29 2007 at 21:02 | IP Logged

Thank you all who commented on my search for the proper steering fluid.  I thought I should tell you what I found.  First, Jim Ferguson (on UnifliteWorld) told me about Aeroshell, a thin red oil (obsolete Mil H 5606 A, Code 60421, “fluid #4”) that could be had from a local airport for about $8/gal.  Not bad since I only need about a pint.  Then, Joey joined that idea by telling me his (boat) uses Mil H 5606 A Hydraulic Fluid (same stuff).  Next I received about four or five messages that said their systems used ATF or power steering fluid, that includes Dave/MV Gizmo of this forum.

Jim Ferguson also told me that the steering units were made by Teleflex.  I checked and sure enough, my steering units (pumps) are made by Teleflex.  So I contacted Teleflex, told them what I had heard and asked them what I should use.  Marc, at info@teleflex.bc.ca answered with, “Please only use SeaStar Steering Fluid (available at your local marine parts store).  You will notice that the fluid is clear in color, but it is fine to mix with what you have in there already.”  Marc went on to say, “The Aero Shell is the same as ours whereas the ATF is not.  ATF will not cause any seal damage, but, it will eventually lead to sludge in the system and hard steering.”

So, it sounds to me, that I have light oil and I intend to purchase either SeaStar or AeroShell.  It also sounds like some systems use ATF, and that’s fine too.