[pjr710]

OK hopefully this can help a lot of people. I researched like tons, called the stealership, etc.

I have one of these magical CHF11S stickers placed on top of an etched in ATF label on the cap.

I plan on doing the power steering flush tomorrow. I siphoned it out just now into a clear container and put a light underneath only to find the color was red!

Photos are below .... at this point what are my options? Can I flush the system and use CHF11S .. or do I get ATF forever now?

For the record my build is 01/2007 e92 ... my cap has ATF on it with a CHF 11s Sticker over it. I called the stealership and gave them my vin and said my car calls for CHF 11s. I 100% have ATF in there now right? Since its red???

[gbalthrop]

Originally Posted by pjr710

...I have one of these magical CHF11S stickers placed on top of an etched in ATF label on the cap...

According to Bentley, page 320-14 (p.537 of pdf), the fluid to be used depends upon the make of your steering rack, Pentosin CHF 11S for the ZF rack, and Dexron III for TRW rack. Look for a label on the rack. The reservoir cover could be a replacement, or the rack could have been changed since original, or WHO KNOWS who worked on it in the past?!?!

George

[pjr710]

Originally Posted by gbalthrop

According to Bentley, page 320-14 (p.537 of pdf), the fluid to be used depends upon the make of your steering rack, Pentosin CHF 11S for the ZF rack, and Dexron III for TRW rack. Look for a label on the rack. The reservoir cover could be a replacement, or the rack could have been changed since original, or WHO KNOWS who worked on it in the past?!?!

George

I never saw that part ... and this is the first time hearing about two different rack manufacturers. I just researched and don't even know how I would tell which I have?

that section contradicts itself because it says to fill with what the cap says multiple times https://www.screencast.com/t/KdSPXsq20

AND what if i do have a ZF rack? But atf in it .. how do i proceed?

[Efthreeoh]

Your car uses CHF-11S, all E9X do. The reservoir cap is the same part for all those years except the current P/N 32416851332 has the green CHF-11S sticker on it. Flush the system and use CHF-11S. Just to confuse things, Pentosin has a compatible replacement fluid for CHF-11S called CHF-202. P/N 32416851332 is listed for use on all E9X models as is the P/N for steering rack.

BMW has been using the same PS fluid reservoir (physical part) for over 38 years, all the way back to the E28 5-series of 1980. Researching the oil reservoir part numbers in RealOEM.com shows BMW ended the reservoir that used ATF for cars such as the E28, E30, E36 etc. and now only uses a reservoir noted for "CHF-11.S". All of the old E28, E30, E36, etc. models used ATF as the power steering fluid. I know that for a fact because I owned a 1989 E30 for 18 years and I own a 1997 E36 Z3 Roadster, both use Dexron ATF power steering fluid.

If ATF was used in your system, it didn't hurt anything. Pentosin says not to mix CHF-11S with ATF, but that doesn't mean if the system was flushed of CHF-11S and ATF used as a replacement it damaged the system. Fresh CHF-11S is dark green. Used CHF-11S comes out pretty much brown if it's been in the system for a long time.

[pjr710]

Originally Posted by Efthreeoh

Your car uses CHF-11S, all E9X do. The reservoir cap is the same part for all those years except the current P/N 32416851332 has the green CHF-11S sticker on it. Flush the system and use CHF-11S. Just to confuse things, Pentosin has a compatible replacement fluid for CHF-11S called CHF-202. P/N 32416851332 is listed for use on all E9X models as is the P/N for steering rack.

BMW has been using the same PS fluid reservoir (physical part) for over 38 years, all the way back to the E28 5-series of 1980. Researching the oil reservoir part numbers in RealOEM.com shows BMW ended the reservoir that used ATF for cars such as the E28, E30, E36 etc. and now only uses a reservoir noted for "CHF-11.S". All of the old E28, E30, E36, etc. models used ATF as the power steering fluid. I know that for a fact because I owned a 1989 E30 for 18 years and I own a 1997 E36 Z3 Roadster, both use Dexron ATF power steering fluid.

If ATF was used in your system, it didn't hurt anything. Pentosin says not to mix CHF-11S with ATF, but that doesn't mean if the system was flushed of CHF-11S and ATF used as a replacement it damaged the system. Fresh CHF-11S is dark green. Used CHF-11S comes out pretty much brown if it's been in the system for a long time.

so from the pic above would you say I have ATF in there now?

If i need to do a flush, whats the best method? The methods I know of are:

1. Drain banjo bolt
2. Drain hard line bolt
3. Turkey baster method
4. Disconnect return hose, put it in a container, start car, drain fluid, stop, repeat until new fluid is coming out

Not sure which actually flushes the system the best. I'd imagine 4.

What if I kept ATF in it?

Also why would my car have ATF in it? I have 120k on my car now .. I am the second owner - bought it at 20k. To my knowledge no one has ever changed PS fluid.

[banglenot]

This might be a time for your favorite indy to inspect and confirm which mfgr rack is installed.

On another German car, this vid notes a physical surface difference between a TRW and ZF rack.

Don't know if it applies anymore.

Might help, if, as GB says, a TRW replacement was used in a repair and that TRW needs ATF (not clear if it does, since it would be odd to require a part sold as OEM replacement use a completely different fluid). You could call a couple of the BMW parts houses where TRW racks are sold as replacements and talk to their parts people. FCPEuro, OEMbimmerparts and similar should be able to chase down the question.

Of course, it's possible that someone added the wrong fluid to a ZF, as well. If it is a ZF, yes you should drain it and replace. Use the newtis at their discussion of pump and rack replacement to check best line to open to drain the fluid.

Also, the reservoir has a filter in it that gets restricted over long periods of old fluid. Cheap replacement, so do it when you do the fluid. $25 or so.

[banglenot]

This might be a time for your favorite indy to inspect and confirm current status.

On another German car, this vid notes a physical surface difference between a TRW and ZF rack.

Don't know if it applies anymore.

Might help, if, as GB says, a TRW replacement was used in a repair and that TRW needs ATF (not clear if it does, since it would be odd to require a part sold as OEM replacement use a completely different fluid).

Of course, it's possible that someone added the wrong fluid to a ZF, as well.

If it is a ZF, yes you should drain it and replace. Use the newtis at their discussion of pump and rack replacement to check best line to open to drain the fluid.

Also, the reservoir has a filter in it that gets restricted over long periods of old fluid. Cheap replacement, so do it when you do the fluid. $25 or so.

[pjr710]

I’m going to look at my rack. It should say ZF on it.

I have a new reservoir here with me. I’m likely going to use the flush method by cycling the old fluid out through the return line into a catch can.

I read the DIY on m3 post as well and they said you don’t need the car on to move the fluid so that’s likely what I’ll do.

Step 1 is verifying my rack says ZF on either the pump the label or both

[Efthreeoh]

Originally Posted by pjr710

so from the pic above would you say I have ATF in there now?

If i need to do a flush, whats the best method? The methods I know of are:

1. Drain banjo bolt
2. Drain hard line bolt
3. Turkey baster method
4. Disconnect return hose, put it in a container, start car, drain fluid, stop, repeat until new fluid is coming out

Not sure which actually flushes the system the best. I'd imagine 4.

What if I kept ATF in it?

Also why would my car have ATF in it? I have 120k on my car now .. I am the second owner - bought it at 20k. To my knowledge no one has ever changed PS fluid.

Looking at your pics, I think you just have dirty Pentosin CHF-11S. Being that BMW N.A. has no recommended service interval for PS fluid, you can rest assured there is no issue with your power steering system and if you've owned the car since 20,000 miles. If the rack was replaced under warranty before 20,000 miles (very rare) the BMW tech at the dealer would have used CHF-11S for the repair. The fresh green CHF-11 goes brown over time and probably looks red to you when light is put on it. Fluid color is really no judge of the contamination level of it; this is true for any automotive fluid.

PS flush in my opinion, is an internet-derived mythical maintenance item. That said, I've done mine twice just for fun (because I like to wrench on my cars), but I have a lift, so draining the system is easy. I've done mine at 151,000 and 264,000. I'll change it again sometime soon around 360,000 I guess. [For my wife's Z3 I replaced the AFT PS fluid just a few years a ago after 19 years because I had to remove the PS reservoir to do some engine work]. Being I have a lift and shop air, I open a banjo bolt on the rack AND open the hardlines that move the fluid to both sides of the piston. I use low pressure air to clear the system of old fluid. Doing that, though, makes for hell of a racket as the system gets fluid back in it and purges the air out. It probably does more harm than good to run it dry like that, which is why I don't do it often they way I do it. If you remove the hardline flarenuts you must be very careful to re-seat them properly so they do not cross-thread the fitting in the rack. It is easy to screw that part up and cross-thread the fitting; the lines put a side-force on the nuts, which tricks you into thinking they are threading correctly when they are not. On a lift it is easy because you are in the correct position to get the feel and proper sight on the nut to see/feel that the flare nut is threading properly. Lying on your back, I'd think makes for a much higher risk of cross-threading the nut. The lines are close to the crossmember, which makes for a tight access to the flare nuts. And use a flare nut wrench so you don't strip the nut flats. IIRC it's a 10MM nut.

It's wasteful, but using a turkey baster to keep removing the old fluid is the easiest method and the less stress on the system (by not running it dry). But I'd imagine it takes several cycles. Most auto parts stores sell a mechanics "turkey baster" - I have a stainless steel one, which has a auto fluid-safe rubber bulb. If you can easily remove the underbelly, and have the proper tools, open the PS reservoir cap and open a banjo bolt on the rack to drain the system. Button it up and then refill the system and purge the air out. The best way to purge the air is to first, with the car raised and the front wheels off the ground, turn the steering wheel all the way left and right without the engine running. Then start the engine and work the steering wheel back and forth.

My 2 cents on the subject. Good luck with it.

[Efthreeoh]

Originally Posted by pjr710

I’m going to look at my rack. It should say ZF on it.

I have a new reservoir here with me. I’m likely going to use the flush method by cycling the old fluid out through the return line into a catch can.

I read the DIY on m3 post as well and they said you don’t need the car on to move the fluid so that’s likely what I’ll do.

Step 1 is verifying my rack says ZF on either the pump the label or both

I'm sure that the Bentley service manual says what it says and it is probably language in their BMW instructions database for another BMW model; they cut and paste like everyone else does...

I've checked the part numbers for the E9X, there are two P/Ns for the rack, both are ZF steering racks. From what I can tell, one P/N is the number for a refurbed rack (32106777463), and the other part number (32106777459) is for a new rack. Your car is a 1/2007 build, just a few months after my 05/2006 build, my car uses CHF-11S. The same rack is used for all E9X (you can check realOEM to verify*). You need to understand that if BMW were to use two different suppliers for steering racks, both would use the same fluid. The production costs to track different production runs of the same 3-series model using steering racks that use different PS would be enormous and no manufacturer would do that. Your car uses CHF-11S.

* rack use in E90/E92

[pjr710]

yea this is all good advice .. i've been researching ... i think its a stretch to have CHF11S be red. It was def red not dirty brownish.

My next step is i'm going to identify it by smell. I hear CHF11s smells like grape cought syrup? ... this fluid I have does not. I just changed my tranny and diff fluid .. i'd say it has more of a strong odor like the diff fluid did if anything.

also what are you talking about bleeding the system dry? If I was gunna do a swap I think I'd get the return hose and put it in a catch can, top up the resevoir, keep it topped off, and just cycle the system until the fluid coming out of the return was the new fluid.

That seems like one of the most efficient ways.

[Welcome to NBA Jam]

You could send it off for an oil analysis and find out, but it'd cost you $20-30.

[ctuna]

My 06 has that green sticker on it to .
And its coming off.
I have done the turkey baster change on it
once with Pentosin chf-11

[CTinline-six]

I would just change out as much as you can with CHF11s and you should be good to go.

[pjr710]

Originally Posted by CTinline-six

I would just change out as much as you can with CHF11s and you should be good to go.

I think that's what i'm gunna do.. i have a ton of CHF11s ... I'm gunna do it by removing the return line keeping the car off and cycling out all the old fluid with the CHF ...

[Efthreeoh]

Originally Posted by pjr710

yea this is all good advice .. i've been researching ... i think its a stretch to have CHF11S be red. It was def red not dirty brownish.

My next step is i'm going to identify it by smell. I hear CHF11s smells like grape cought syrup? ... this fluid I have does not. I just changed my tranny and diff fluid .. i'd say it has more of a strong odor like the diff fluid did if anything.

also what are you talking about bleeding the system dry? If I was gunna do a swap I think I'd get the return hose and put it in a catch can, top up the resevoir, keep it topped off, and just cycle the system until the fluid coming out of the return was the new fluid.

That seems like one of the most efficient ways.

I mean, if you disconnect the lines you can drain most all the fluid out and the system for a few seconds runs without being fully filled with fluid.

[pjr710]

I'm gunna do this with the car off

[bluewater328]

Originally Posted by pjr710

I'm gunna do this with the car off

Oh look, a whisky tasting