I recently installed a new power steering pump, as well as pressure hose. I noticed that the pump is fairly noisy, there is a slight shudder that I can feel and hear coming from inside the cabin of the car- like a rattle.

My fluid levels are fine, I have no leak.

My transmission mount on that side is fairly old. Aside from that possibility, I'm not sure why the pump is noticeably louder than the one I removed. Any ideas?

Thanks

 

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There may be air in the PS system that is causing your noise.
After the parts were replaced and the fluid reservoir was filled to the upper line, did you bleed the air from the system by turning the steering wheel, from lock to lock, several times while the engine was running?