Sunday, September 7, 2008

Tech Tip: Power Steering Fluid

The power steering systems for the 1955-1957 Thunderbirds were designed to run on Type A transmission fluid. Since Type A transmission fluid is no longer available, many Thunderbird owners and their mechanics have used power steering fluids in their Thunderbird steering systems. Power steering fluid will work in your car's system, but by using regular power steering fluid your system is subject to developing leaks. This is due to the fact that power steering fluid is "thinner" than Type A transmission fluid. The "thinner" fluid is able to leak out of the seals, central valve, and cylinder. The solution to this problem is to once again use transmission fluid in your Thunderbird's power steering system. Though Type A transmission fluid is no longer available, Type F or FA transmission fluid is available and is an acceptable substitute.

Since Ken Smizinski has supplied this important maintenance tip, I asked him what a Thunderbird owner should do if he has been using standard power steering fluid in his Thunderbird. Ken recommends that to insure that the system has not been damaged or compromised, the power steering system should be drained completely, inspected, and refilled using the above recommended transmission fluids. Since draining the system completely introduces air into the system which can render your system inoperable if not removed completely, this complete change in fluid should only be done by a qualified mechanic! This is not a job for someone like me, your typical "dangerous" do-it-yourselfer. Make sure you know your own "mechanical" limitations. A Bird, and its owner, are a terrible thing to waste!!!

As an alternative to complete replacement, the less preferable option is to start using the above transmission fluids as you need them. Remove as much of the power steering fluid as you can from the reservoir and replace it with the appropriate transmission fluid. As you run low on fluid continue to add transmission fluid. Power steering fluid can be mixed with transmission fluid. If your lucky, you will eventually have enough transmission fluid in your system to stop any leaks caused by using power steering fluid. This fluid change over, however, will not fix any leaks in your system caused from old, hard seals, worn out pumps, and other problems associated with an aging system. If your car, however, has a new power steering system, yet you have leaks, this tip may solve your problem. Good luck, and remember your own "mechanical" limitations!!!

Source: CTCC Tech-Tip Manual 1993-1997


Anonymous said...

Type A,F,FA are still avaiable.
I purchasedd a case of each through my local Auto Value last summer {june'10}. Took a week to come in.

CarDoc2020 said...

Type A trans fluid is most certainly still available; just walk into most any gas station/convenience store/grocery store and grab the cheapest bottle that says only "Transmission Fluid" on the front. Look on the back of the bottle and it will more then likely say "Type A"!! Type A was replaced by Type A, Suffix A, then Dexron, Dexron II, Dexron III, then Dexron III/Mercon (Dexron being the GM spec and Mercon the Ford spec). All are acceptable. Mercon is speced in most Ford power steering systems through the 2000s.

CarDoc2020 said...

Trans fluid school part 2. Type F (and the later FA [also blue B&M fluid]) is NOT compatible with Type A and the later Dexrons: the coefficient of friction modifiers are opposite. Ford designed Type F be sticky for a crisp, positive shift whereas GM designed Dexron to be slippery for a smooth shift. Never mix the two as the different friction modifiers, acting against each other, will cause the friction material to be ripped from the clutch discs in short order. I don't know what that will do to power steering seals but probably not good!!

Unknown said...

I Kind of agree with the author that to fix these kind of problems we have to take the car to a capable mechanic rather than do it on your own. The cost may actually increase if you botch up the job, so get to the professionals to do the job