1998 S90 Power Steering Fluid

[kbmusic]

Hello everyone,

While doing a routine inspection on my car (1998 S90) yesterday, I noticed that the power steering fluid was slightly low (it was almost exactly on the "ADD" line when the engine was cold). This is the first time I've had to add any power steering fluid since I've owned the vehicle (about a year), and I remembered seeing something in the owner's manual that indicated the use of ATF fluid in the power steering pump instead of conventional power steering fluid. I double-checked, and sure enough, the manual specifies "ATF Type F,G" for the power steering. (Note: For the automatic transmission, the manual specifies "ATF Dexron IIE/III and Mercon").

Obviously, my instinct tells me to use ATF Type F, since that is what the manual indicates, and since they made a clear distinction between Type F for the PS and Dexron for the AT. The fluid currently in the reservoir is red, so I'm fairly certain there is already some type of ATF fluid in there, and I've never had any problems whatsoever with the power steering system. However, I tried to search on this forum (and others) just to be sure and found a lot of conflicting information. I wasn't able to find a thread specifically dealing with a '98 S90, but on threads for older 960's, some people said to use Type F, others said it was okay to substitute Dexron, and still others said to absolutely NOT use Type F. Does anybody have a definite answer on this? Any recommendations on a specific brand of ATF? Thanks!

[regent]

You cannot go wrong if you follow the OEM specs.

If you are indeed losing fluid, you will need to find out why. Check for leaks inside the rack bellows to make sure you don't have failing seals. Inspect the system lines and connections, and look at the PS pump for signs of seepage through its drive-end seal

[kbmusic]

Thanks for the reply!
I'll be out there later this afternoon to try to locate the leak. Whatever it is, it's a very slow/small leak (for now) so hopefully I'll be able to spot it, and hopefully it's something simple (like the return line) and not something more complicated (like a problem with the pump or rack).

[xHeart]

ADD marker at the cap can be elusive. Run the engine without the cap, take a visual reading.
Make sure you fasten the boots back on firmly.

Meanwhile, several at MVS talk about Valvoline Max Life, I use it in recently installed rebuild rack, the label reads as follows...

Valvoline Max Life label

MVS_0756.jpg (484.83 KiB) Viewed 2643 times

[kbmusic]

Thanks! I've used several Valvoline MaxLife products in the past and have been very happy with them. Since I was just adding a very small amount to bring the level in the reservoir back to normal (it literally took only about 50-100ml or so) I used Type F ATF fluid. Although I doubt it would make any real difference, I would still be a little nervous using Dexron/Mercon fluid (the MaxLife label shows compatibility with Ford's "Mercon" fluid, and four different Volvo-spec fluids, but not Ford's older "Type F" fluid.) Also, I can only assume that the previous owner used Type F as specified in the manual, and it would probably be unwise to mix different fluid types regardless.

[wildbill96]

Thanks for these posts!
This is my first visit to MVS. We had rack seals replaced 2 or 3 times on our 98 S90. Perhaps now I know what is wrong -- wrong fluid!