M3 power steering fluid [Archive] - Bimmerfest - BMW Forums

: M3 power steering fluid

middleton m3
12-30-2005, 11:59 AM
i have a 97 M3, i know nothing about cars and need some help, its been making a noise lately like a loud humming noise from up front when i slow down to take a turn or have to stop, it goes away when the cars driving and if i come to a really slow stop it tends not to do it as opposed to when i come to a quick stop and the noise gets pretty loud. i thought brakes at first but checked and they appear to be fine. my friend told me it sounds like it needs power steering fluid, i looked but cannot find a power steering fluid cap. where do i check to see if i need power steering fluid ?

12-30-2005, 12:55 PM
The power steering resivoir is on the drivers side of the engine bay and down. You'll see a black cap down there, take it off (it's a bit hard to unscrew). This cap is also the dipstick, if it reads low, or you can see that the fluid in the resivoir is low, then add fluid. The cap should say ATF fluid only.

12-30-2005, 06:16 PM
Depending on how many miles, might not be a bad idea to suck out all the old fluid and fill with fresh.

10-27-2008, 02:37 PM
i had the same noise on my 95 m3. check/listen under the hood and rev the engine. if u hear like a banging near the engine head it could be the chain tensioner.

10-28-2008, 04:30 AM
Depending on how many miles, might not be a bad idea to suck out all the old fluid and fill with fresh.Definitely. Mine (100k) was a dirty brown color. A quart of synthetic ATF is like $6, fill it, run a week or so, and repeat a couple of times to flush it out.

11-07-2008, 09:44 AM
Definitely what the above said. If your P/S is humming, it's not circulating well and is probably caused by a lot of dirt in that old fluid.

Do a flush, and if you're not comfortable doing it, a service shop can have it done for you for a reasonable price.

Also, make sure there aren't any leaks. My M3's rack was leaking once b/c of the stupid line having a split in the metal collar, so I just cut it off and pulled it out and replaced it with a new hose and regular clamp.

11-07-2008, 03:19 PM
Remember that the reservior has a built in filter. That is the thing that sits above the reservior can and if that is plugged exchanging the fluild will not help. It would have to be pretty bad for that to happen.
I used a turkey baster to remove old fluid and put in new fluild. I will do this about 3 times unless I crack a banjo bolt from the rack to let it all drain out that way. It is good advice and very cheap to do.