Shamrock W126

I suspect my power steering fluid is low. When I steer from straight to either side, I get a gentle vibrating rumble sound. When the steering wheel is turned back to straight, the sound goes away.

I have noticed a consistent leak around one of the hoses going to the steering box, and will replace the hose once it comes in on Friday. Till then, I was hoping to top off the fluid and get better (normal) steering performance.

Question is - how do you check the level, or know how 'full' to fill the reservoir? When I unscrew the black knob and remove the aluminum top, there is no dipstick or min/max markings.

Any ideas?

Shamrock W126
'85 300SD 413,865
'98 ML320 245,660

blowfish

when u see lots of oil in there it should be Ok, if its low then u add.