PS Fluid
02-12-2004, 07:35 PM
#1
Burning Brakes
Thread Starter
Join Date: Dec 2002
Location: Airlie Beach, Australia
Posts: 870
Likes: 0
Received 0 Likes
on
0 Posts
PS Fluid
Hi,
a recent exchange on the 928 Rennlist E-mail area has prompted this - I hope it is of some value
The content ( "language" modified ) was posted on the Landsharkoz site some time ago
Starts:
Often forgotten THE POWER STEERING SYSTEM ( PS ) is a vital safety part of ANY car
IT IS VERY LIKELY THAT MANY 928'S WILL STILL HAVE SOME IF NOT MOST OF THE ORIGINAL FACTORY FILL FLUID IN THE PS RIGHT NOW!
IT IS ALSO MOST LIKELY TO BE CONTAMINATED EITHER WITH UNKNOWN FLUIDS OR WEAR METALS!!
A few months after I purchased my first MY81 - 928 several years ago I carried out a routine check of the PS fluid The reservoir's top was tight so I had to use a bit of force, the reservoir turned a little, the top came off and the fluid level was where it should be and the fluid was in good condition.
Later that day and close to home I stopped and then noticed a small puddle of dark fluid. I checked the PS reservoir and it was down - a slow 1 km trip to my pet wrench. We replaced all hoses - they were hard and a real risk - a lesson learned
Sadly the PS is most often neglected, often topped up with "unknown" liquids and yet it has a real influence on the life of a costly part of the vehicle as well
I CHANGED MY S4'S PS FLUID SOME TIME AGO AND WAS AMAZED AT ITS POOR CONDITION! IT NOW HAS A SYNTHETIC ATF DEXRON 3 INSTALLED WITH GREAT RESULTS
The correct lubricant for your PS is the same ATF as is used in the Auto transmission with Dexron 2 or 3 compliance - the Dexron 3 is better
It should be noted that the PS's fluid operates at around 75bar and up to 100bar.It gets quite hot, operating around the 80-90>C range at times due to the high operating pressures and of course its location on the vehicle. And the 928 has no PS oil cooler
Check the PS's fluid level regularly and check for leaks or damaged /cracked hoses. The hose checking is best done with the motor running and with someone else turning the steering wheel to full lock, RH then LH, holding each for a 10-15 seconds. Especially check the pressure hose ( whenever possible ) for deterioration or leaks and replace all hoses if any one hose is suspect.
Do not overfill the PS reservoir!
The power steering's ATF should ideally be changed every 2 or 3 years or when you change the transmission's ATF even though no parameters were apparently set for this by Porsche
IF YOUR SYSTEM IS LEAK FREE PERHAPS IT IS TIME TO CHANGE THE FLUID NOW
One easy way for the handyman to change the fluid is to use a suction pump to withdraw the existing fluid from the reservoir ( it holds about 300ml ) topping up each time and then running the car for a day or two in between
Do this 5 or 6 times and you will have most of the old ATF removed and you will also have flushed the system in a gentle way at the same time. It will require about 1.75 litres to end up with a flushed
out system and to end up with brand new "known" fluid in place
Now, if you are already using a synthetic ATF ( like Castrol's Transmax Z ) in your Auto the good news is that you can also use it for the PS when changing, especially if there are no leaks or any "loss" of the current fluid
Most synthetic ATF's are compatible with other Dexron 3 ATF's and the small amount remaining is insignificant
You can at the very least double the PS's fluid change interval ( to say four years ) if using Transmax Z - double it?
Well it's change cycle was never noted anyway so doubling the unknown is very easy!
Ends.
Regards
a recent exchange on the 928 Rennlist E-mail area has prompted this - I hope it is of some value
The content ( "language" modified ) was posted on the Landsharkoz site some time ago
Starts:
Often forgotten THE POWER STEERING SYSTEM ( PS ) is a vital safety part of ANY car
IT IS VERY LIKELY THAT MANY 928'S WILL STILL HAVE SOME IF NOT MOST OF THE ORIGINAL FACTORY FILL FLUID IN THE PS RIGHT NOW!
IT IS ALSO MOST LIKELY TO BE CONTAMINATED EITHER WITH UNKNOWN FLUIDS OR WEAR METALS!!
A few months after I purchased my first MY81 - 928 several years ago I carried out a routine check of the PS fluid The reservoir's top was tight so I had to use a bit of force, the reservoir turned a little, the top came off and the fluid level was where it should be and the fluid was in good condition.
Later that day and close to home I stopped and then noticed a small puddle of dark fluid. I checked the PS reservoir and it was down - a slow 1 km trip to my pet wrench. We replaced all hoses - they were hard and a real risk - a lesson learned
Sadly the PS is most often neglected, often topped up with "unknown" liquids and yet it has a real influence on the life of a costly part of the vehicle as well
I CHANGED MY S4'S PS FLUID SOME TIME AGO AND WAS AMAZED AT ITS POOR CONDITION! IT NOW HAS A SYNTHETIC ATF DEXRON 3 INSTALLED WITH GREAT RESULTS
The correct lubricant for your PS is the same ATF as is used in the Auto transmission with Dexron 2 or 3 compliance - the Dexron 3 is better
It should be noted that the PS's fluid operates at around 75bar and up to 100bar.It gets quite hot, operating around the 80-90>C range at times due to the high operating pressures and of course its location on the vehicle. And the 928 has no PS oil cooler
Check the PS's fluid level regularly and check for leaks or damaged /cracked hoses. The hose checking is best done with the motor running and with someone else turning the steering wheel to full lock, RH then LH, holding each for a 10-15 seconds. Especially check the pressure hose ( whenever possible ) for deterioration or leaks and replace all hoses if any one hose is suspect.
Do not overfill the PS reservoir!
The power steering's ATF should ideally be changed every 2 or 3 years or when you change the transmission's ATF even though no parameters were apparently set for this by Porsche
IF YOUR SYSTEM IS LEAK FREE PERHAPS IT IS TIME TO CHANGE THE FLUID NOW
One easy way for the handyman to change the fluid is to use a suction pump to withdraw the existing fluid from the reservoir ( it holds about 300ml ) topping up each time and then running the car for a day or two in between
Do this 5 or 6 times and you will have most of the old ATF removed and you will also have flushed the system in a gentle way at the same time. It will require about 1.75 litres to end up with a flushed
out system and to end up with brand new "known" fluid in place
Now, if you are already using a synthetic ATF ( like Castrol's Transmax Z ) in your Auto the good news is that you can also use it for the PS when changing, especially if there are no leaks or any "loss" of the current fluid
Most synthetic ATF's are compatible with other Dexron 3 ATF's and the small amount remaining is insignificant
You can at the very least double the PS's fluid change interval ( to say four years ) if using Transmax Z - double it?
Well it's change cycle was never noted anyway so doubling the unknown is very easy!
Ends.
Regards
02-12-2004, 08:06 PM
#2
". And the 928 has no PS oil cooler"
Actually there is a small one (on the S4 anyway)...a long metal loop that runs in front of the ac/condensor radiator. Lies flat right in front of it.
And you cannot get it in there without removing the rad.....
later,
Tom
midlman@rennlist.com
89Gt
87S4 AT
Actually there is a small one (on the S4 anyway)...a long metal loop that runs in front of the ac/condensor radiator. Lies flat right in front of it.
And you cannot get it in there without removing the rad.....
later,
Tom
midlman@rennlist.com
89Gt
87S4 AT
02-12-2004, 10:59 PM
#4
Racer
Doug
I need to replace the ps hose which goes towards the engine. I am currently in the middle of my 1st TB change and thought it might be a good time to do this also. Do you have any recommendations since I cannot run the car while the tb change is in progress. Might it be better to wait until the tb is finished?
Thanks
Doug
I need to replace the ps hose which goes towards the engine. I am currently in the middle of my 1st TB change and thought it might be a good time to do this also. Do you have any recommendations since I cannot run the car while the tb change is in progress. Might it be better to wait until the tb is finished?
Thanks
Doug
02-12-2004, 11:22 PM
#5
Nordschleife Master
The suction hose for the pump? (tank to pump)
Or the pressure hose from the pump the rack?
Or the return from the rack to the tank?
(I just did this!)
(And then i just realized your dealing with an 88, and it may not be the same. Sorry.)
Or the pressure hose from the pump the rack?
Or the return from the rack to the tank?
(I just did this!)
(And then i just realized your dealing with an 88, and it may not be the same. Sorry.)