Groaning from steering system

[CorvallisBMW]

My convertible has developed a weird groaning/humming from somewhere under the hood, and it seems to be related to the steering.

-It only happens when the car is cool or cold, not when fully warmed up.
-It only happens when I turn the wheel while moving in reverse.
-It doesn't happen then backing straight up or if I turn while moving forward.

This is an e36 rack, the fluid is full and fairly new. It sounds like it could be related to the pump, I'm not sure what else would make such a loud humming noise. But I'm not sure why it only shows up during this set of circumstances.

Any ideas?

[CorvallisBMW]

Anything? Anyone?

[Wh33lhop]

Absolutely sure the reservoir is full? Is it a new reservoir/filter?

Mine looked "full enough" but was actually draining the fluid when I turned it on/used the steering and aerating it up, which would cause a big ruckus (especially when cold). Filled it all the way up with ATF and now it's smooth as silk.

If it's full but it's an old reservoir you may want to change it out for a new one to change the integrated filter.

[E30_Pare]

mines doing the samething. Just topped off the fluid, and good as new.

[CorvallisBMW]

Good to know. i'll buy a new reservoir/filter today. It leaks anyways.

[brian90]

I would try a power steering flush too. I know on other vehicles after a flush the noise usually goes away. Something to think about I guess, hope the reservoir and filter will fix it. Good luck.

[ck_taft325is]

Mine made near the same sound and only in reverse, like yours. I ended up replacing the hoses and topping it off. Then, while on jack stands rotating the front wheels lock to lock to make sure all the fluid was in the rack and the appropriate amount was in the resevoir. After a steering rack change (Thank you Joe318is for this info), you should turn lock to lock a few times to get an accurate idea of how much more ATF you need in the resevoir. Mine drained after filling and going lock to lock a few times to nearly empty. It wasn't leaking, just filling the system entirely. Haven't dropped at all since I did the above mentioned procedure. Hope it helps!