what causes moaning in steering system?
Many possibilities. First check your fluid level in your power steering pump.
With the motor running have someone turn the steering wheel and watch to see if pump belt is slipping. If both the above are normal, your rack might be going bad or other front end parts which requires a mechanic to diagnose.
First thing is to check your PS fluid. You may have a leak and now are low.
Yosemite
04 vue has no hydraulic power steering boost. it is elec boost. look under the dash for the elec assist module. that being said, a “moan” could be something in the rack bellows rubbing? hmm, gotta go look. i replaced my intermediate steering shaft last month. quite easy. but that is too fix the common vue/nox steering rattle issue. i do see quite a few elec modules missing from boneyard vues/nox’s. not sure why. never heard that they fail.