Really.. which power steering fluid the 4.8is uses?

[xRide]

All along I thought it was ATF, but I looked at the cap just now and it says CHF-11S. This reservoir was a replacement and I dont remember where I purchased it if it was an original part.

[squidzilla]

CHF 11S is what I think you mean. That is what is in my 545i.
Part Number Search 83-29-0-429-576

These guys have Febi Bilstein for 13.46 each. Free shipping if you spend 65.00 and they ship fast.

[xRide]

Is it that the newer 4.8is has that fluid and the older model has ATF?

My truck is June 2005 built.

[Qsilver7]

Originally Posted by xRide

All along I thought it was ATF, but I looked at the cap just now and it says CHF-11S. This reservoir was a replacement and I dont remember where I purchased it if it was an original part.

The clue to your question is the highlighted text in your quote above.

BMW no longer makes the original ATF reservoir or lid with ATF on it for the generation BMW your 05 X5 falls within. The lid & reservoirs that used CHF 11 S Pentosin hydraulic fluid is what they substitute when a replacement reservoir or cap is required.

The most important thing to look at though...is the color of the fluid inside the reservoir. If it is reddish-pink...then it is indeed ATF. Pentosin CHF 11 S hydraulic fluid is green. And if someone incorrectly mixed the two...then you'd have a light muddy looking concoction in the reservoir...which you'd need to drain immediately.

You can verify the non existence of the ATF reservoir & lid by just looking up the PS reservoir and lid in the part database. Take note in the part nbr index that the only reservoir (item #1) available is listed as for CHF 11 S...and a label is supposed to be ordered that says ATF. Or if you only need the lid (item #2)...there's also a part nbr listed for ordering the label that should be mounted to indicate to anyone working on the vehicle that the PS reservoir contains ATF (not CHF 11 S).

I hope this helps makes sense of everything.

RealOEM.com * BMW E53 X5 4.8is Oil carrier / Single parts

[xRide]

The problem is that I drained fluid and replaced with ATF about 2 years ago so I'm not sure what it was originally was. Again, based on research I thought it was ATF. Is there a sure way to tell based on production date?

Right now it seems my power steering pump is gone or is going because it's making a weird noise and I'm wondering if it's the wrong fluid that caused it to go bad.

[Qsilver7]

Uh...it's always been ATF. Again, the CHF reservoir is the only thing you can get now...which is why BMW has the ATF label to mount in the engine bay when you get a replacement reservoir or lid...and if you clicked the direct link to the part database provided in my reply above...the supplemental info for the reservoir specifically says that the label that you mount in the engine bay to explain that the system uses ATF is sold in CONJUNCTION with the CHF 11 S reservoir.

Unless your X5 was once sold in a BMW market close to or above the Arctic circle...it never came with Pentosin CHF 11 S fluid in the power steering system...it's always been ATF.

[xRide]

Ok got it. Thanks guys.

[electricalserv x5]

Originally Posted by Qsilver7

Uh...it's always been ATF. Again, the CHF reservoir is the only thing you can get now...which is why BMW has the ATF label to mount in the engine bay when you get a replacement reservoir or lid...and if you clicked the direct link to the part database provided in my reply above...the supplemental info for the reservoir specifically says that the label that you mount in the engine bay to explain that the system uses ATF is sold in CONJUNCTION with the CHF 11 S reservoir.

Unless your X5 was once sold in a BMW market close to or above the Arctic circle...it never came with Pentosin CHF 11 S fluid in the power steering system...it's always been ATF.

Right On silver ATF all the way.....You will damage your pump if You don't uses ATF..........

[jfoj]

I believe that CHF is required on vehicles with the active suspension? I also have seen that Advance Auto and some other parts stores now carry Pentosin CHF 11S.

[xRide]

Is the power steering pump a rebuildable part on our trucks or you have to get a brand new one?