Power steering fluid - a simple yes or no

[whiskychaser]

Trying to establish if it is ATF or CHF 7.1 which of course you cannot mix. Hand book says see BMW. Local BMW say they used ATF up to 2001. Bentleys says it could be either. There is no label on the reservoir and the cap just says 'ZF'. ATF is red, CHF 7.1 is green but the stuff in there is yellow! I found sites that said Pentosin CHF 11S is good for 9/91onwards (Pentosin's own site says 1990 on). In fact there is an item in TIS that says BMW went from 7.1 to 11S in 9/91 but that was the E32 (Nods to Shogun). I know you cant mix 7.1 and 11S but you probably cant get hold of 7.1 anymore. I've read if you put ATF into a CHF system it can wreck it (another nod to Shogun) but nothing the other way round. On a UK site I've got a guy with an '88 using 11S and another with a '96 using ATF. The latter says its got ATF written on the reservoir so thats fair enough. Looked at TIS and cant find it. What should have been a damn simple question has turned into a War & Peace. Sooooo before you fall asleep, am I good with 11S? No hedging. You have to say yes or no

[Tiger]

Yellow PS fluid sounds like aftermarket PS fluid... regular PS fluid is clear, yellow color... Not sure what you have in yours at this point.

Amsoil says your car uses ATF and they recommends their synthetic ATF.

AutohausAZ says CHF 11S only if your car specifies it...

You can still buy 7.1... or you can buy alternative Febi Green... which is cheaper than Pentosin...
GermanAutoParts.com

I would just put in Febi Green or 7.1... not 11S or ATF...

You really have to suck out all fluids... You should consider changing or condition your PS hose at the reservoir before pouring new fluid in... at least one hose should be changed... and that hose has no fitting... goes from reservoir to another pipe. This is the hose that leaks 90% of the time. Other hoses that has special fittings... just trim the end of the hose off and clamp on new part of hose. Should be enough room.

[whiskychaser]

Many thanks for that. I will be sorting out both hoses as you described:-)

[glen-sj]

Many thanks for that. I will be sorting out both hoses as you described:-)

I have a 92 525ia and it uses ATF and a 95 530ia and it uses CHF 11.

[632 Regal]

dont matter the color in there now, rely on the manual and the sticker. all other guesses are luck of the draw.

[genphreak]

If PS only (E.g. not an LAD/EDC equipped car), you can swap from 7.1 to ATF, but must replace all the fluid to do it. I have not tested this in freezing conditions, but if you use use Synthetic ATF such as Castrol Transmax-Z, it should be okay.

[whiskychaser]

If PS only (E.g. not an LAD/EDC equipped car), you can swap from 7.1 to ATF, but must replace all the fluid to do it.

I read that. There is so much conflicting information around about what should be a no brainer. I've got litres of Dexron III kicking around for the auto tranny but in the absence of a label or marking on the cap I'm reluctant to use it. My local factors only stock 11S and you will faint if I tell you what it costs But I'd rather pay more and not have nagging doubts about pump or steering box seals. Whatever is in there now will be flushed out

[genphreak]

Yea, I've done it in an M50, 2 years ad still going strong . Use Dexron III if you must, in PS system it makes no diffference- except that synth never breaks down. You'll be fine swapping it out. Use the previous advice tho, change the leaky hoses whilst doing it .

[whiskychaser]

Feed hose was fine -just fitted new clips. Got return hose free from a hydraulic hose company Old stuff looked yellow when I dipped it with a bit of kitchen roll. Looks black in a bottle. Anyway, flushed it and refilled with CHF11S. Doesnt feel any different. But I got rid of the old stuff and dont have any leaks so thats a result

[Tiger]

My return hose was rock hard and leaking like .