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Pulsating grinding noise from under the car

2000 Hyundai Elantra. Lately, the front driver side which has a new wheel bearing, makes a pulsating grinding noise when the engine is cold. The grinding noise goes away after a few minutes of driving and does not return until everything is cold again. The noise is even louder if I rotate the
steering to the right. Rotating the steering to the left makes the noise almost go away. It started happening a few days after I rotated all 4 tires. The pulsating grinding noise is new, before it was a constant humming grind when the engine was cold, not so loud, that eventually went away after driving for 30 minutes or so. The weird part is that the new pulsating grinding noise goes away after driving the car for a minute or two. Is it related to alignment or something else?

Is the noise only In gear and moving down the road, or also when idling?

The grinding noise appears when the car is cold and the speed hits 20 MPH for the first time and then goes away after a few miles of driving and does not return until everything is cold again.

Grinding noises during driving that get worse when turning right and go away when turning left are often a bad wheel bearing on the left side of the car. The steering effect is cause b/c on right turns the weight of the car is thrown more to the left side. CV joints are another common cause. A pulsating sensation that is affected by steering in a similar way can occur with a bad tire, cupping, tread separating etc, but grinding is not consistent with a bad tire usually. Are you able to tell which side or corner of the car the sound is coming from?

You replaced the left wheel bearing? What led you to do that? Noise? Did it go away after you changed wheel bearing? You now have “new” noise? Did nothing improve/change/worsen after you did wheel bearing?

I changed the front driver side wheel bearing because of a different noise. Previously, the tires/wheels had a humming noise which increased and decreased when I turned the steering clockwise or anticlockwise. Judging by the nature, experts told me it is the front driver side wheel bearing that is bad and I changed that wheel bearing. However, that did not fix anything. The noise was still there. I was told to rotate tires. All 4 tires were rotated and balanced 6 days ago. The pulsating, short-term, dragging noise started 3 days ago.

i also had a humming noise. i jacked up front and used motor to spin left and than right wheel. very easy to hear which one was making the sound. new bearing and noise is gone. lift 1 wheel at a time.

@YourMinky

The inner CV joint is a three point ‘tulip’ and if the shaft is pulled out of the tulip and replaced out of its original position the result can be pulsing in a turn and when accelerating. Did you pull the inner joint apart?