DIY: Refresh your Power Steering Reservoir/Hoses, for 10 Bucks

[Ricky Bobby]

Originally Posted by Brandon002

This DIY wouldn't be a "refresh" more like a quick fix for a leak.

Again, I note in the first post to evaluate your reservoir and hoses before doing this. If your hoses are weeping, 14 years old with 200k miles on them and cracked, doing this will not help. I don't recommend this if you already have leaks, if you do, you're right, its more of a quick fix and you probably need to replace the hoses as well.

If you have lower mileage, perhaps a later build X5 and don't live in a huge thermal cycling area, there is good chance if you do the refresh you will not have to touch the PS system for a few years ahead.

This is MY experience on my 2003 with 71k miles, my hoses look great and are pliable and not showing cracks, but the weak factory clamps are a known problem, as is the O-ring on the cap. A cheap and easy way to get some fresh fluid in there and freshen up the system preventatively.


This is why I shouldn't have bothered, now all the analysts are out lol.

[Brandon002]

Originally Posted by Ricky Bobby

Again, I note in the first post to evaluate your reservoir and hoses before doing this. If your hoses are weeping, 14 years old with 200k miles on them and cracked, doing this will not help. I don't recommend this if you already have leaks, if you do, you're right, its more of a quick fix and you probably need to replace the hoses as well.

If you have lower mileage, perhaps a later build X5 and don't live in a huge thermal cycling area, there is good chance if you do the refresh you will not have to touch the PS system for a few years ahead.

This is MY experience on my 2003 with 71k miles, my hoses look great and are pliable and not showing cracks, but the weak factory clamps are a known problem, as is the O-ring on the cap. A cheap and easy way to get some fresh fluid in there and freshen up the system preventatively.


This is why I shouldn't have bothered, now all the analysts are out lol.

It's not a matter of analysts coming out, it's just that this is a very old trick to cure leaking at the clamp area. If you're comfortable with this as a "power steering system refresh" then more power to you.

[JCL]

RB:

Interesting claim from your Bimmerfest source that ATF is hygroscopic. ATF is basically an oil. There may be some small amount of additives in it that have hygroscopic properties, but fortunately, it is not hygroscopic, meaning that it doesn't attract water like brake fluid does. If it did, we would be having to change it much more frequently, like brake fluid, and it would not be recommended to just change the ATF in the reservoir but rather get it all out of the system.

If the top hose deteriorates and seeps, why doesn't the lower connection? Seems like a better idea to replace the hose if there is any apparent deterioration.

[nebilex]

Originally Posted by Ricky Bobby

Note: This only applies to vehicles where you are sure the PS reservoir has no cracks, and the hoses are in good shape from what I have gathered it is a pretty stout piece, and isn't prone to cracking like our expansion tanks. Most replace them because they are cheap comparatively, at 40 bucks for Genuine BMW, or ZF (OEM) for around 25 bucks. My 2003 has 71k miles and the reservoir is basically brand new, hoses going from the reservoir look good as well, not dried out or cracking. This DIY is performed on a 3.0 M54, but process is similar for V8 models. Obviously I am not liable for any damages to your vehicle when following this procedure.

You will need:

1 - Quart of Synthetic ATF (PS fluid, I used Mobil 1) or if your cap says CH-11S on it, use that ($5.99 for Mobil 1 ATF at WalMart)

1 - Size -130 O-ring, pick your poison as far as material goes, personally I used a Fluorosilicone O-ring (military rated, higher temp and chemical resistance than Viton, and its blue! lol) from McMaster Carr, $3.50

2 - Stainless Steel worm drive hose clamps, I forget the sizes but somewhere in the 7/8" range, just measure the diameter of the hoses first, if you prefer your clamps not to "bite" into the hose you can use fuel line clamps which are smooth inside

Tools:
-Utility knife or PVC pipe cutter (great for hose trimming)
-Socket driver or screwdriver for hose clamps
-Turkey baster or siphon for draining reservoir
-Socket for mounting bolts of PS reservoir
-Drip bottle for catching old fluid


1) Open the PS cap, remove o-ring by picking it out with a small knife or screwdriver, throw old o-ring in trash, lubricate new o-ring with fresh ATF or CH-11S, install on cap in groove, set aside for later.

2) Take your turkey baster ($1 at dollar store, then you can throw away after and your wife won't get mad), suck out all fluid in reservoir

3) Unbolt reservoir off its mount, now you have some room to work

4) Use flathead to loosen clamps on bottom of reservoir, place drip bottle underneath, and remove hoses from reservoir 1 at a time, catching the drippings from the reservoir into your catch bottle, and draining the fluid from top of the hose, remove old clamps from PS reservoir hoses

5) Take pipe cutter or utility knife and cut approx 1/2" off the ends of the hoses, make a clean cut and expose a fresh hose end, slide new worm gear clamps over hoses

Optional Step from Miniz Guy if you'd like to replace your hoses but don't want to buy factory ones for $60:

On E36's, the hoses are 1/2" ID. Use transmission hose rated for high pressure applications and you can replace the original hoses for about $10. Cut the original crimp off, but not into the barb, and slip the new hose on with another worm clamp.

The process should be the same on the X5. A little better way that using the old hoses.

6) Reconnect hoses to bottom of reservoir (they are different sizes so you can't mix up), tighten clamps with screwdriver or socket, now is a good time to wipe down the 2 hoses with degreaser, and use a rubber protectant on them, I use 303 Aerospace protectant on rubber items

7) Bolt up reservoir back to its mount next to the Oil filter housing (on 3.0 models), and refill with fresh ATF. There is a dipstick on the cap which has a clear marking for the correct level, don't overfill. Put your cap with new o-ring on the reservoir and check level.

8) Start car, do a couple lock to lock turns, then shut car off and check level on dipstick. Remove some fluid with siphon if too high, add some if level shows low. Obviously check for leaks on bottom of reservoir, but as long as hoses were in good shape, you should have none as long as you exposed a fresh hose end and used new clamps

10) Have a brewski and enjoy not having to mess around with your PS system for a few years!


I have to give credit to bluebee and others at Bimmerfest for the O-ring sizing on the reservoir, this DIY is inspired by their threads and helpful information on the M54 engine, and I thought I'd pass along the information to my fellow Xoutposters, with some preventative maintenance and inspection, a half hour of your time and about $10 in materials, this is an easy procedure to perform if you are doing an oil change or something similar. Hope this is helpful to some!

Thanks Ricky, I actually ended up buying the hose that goes from the reservoir to the pump and a new ZF reservoir for $29. So this should be an easy fix. I will pick up a couple of clamps on my way home and this will be the weekend project.

[Ricky Bobby]

I myself disagree with ATF being hygroscopic, just used that paragraph to show that the filter is serviceable in the reservoir.

Again, if you're showing leaks, the hoses should be replaced.

Making a fresh cut on the ends and using new clamps may buy you a few years as what I've been finding is that the clamp connection goes first, underneath the reservoir.