Pulsing noise/vibration in 2012 Mazda 3 Sedan

[Kat]

I've used the search function and only found one post relating back to 2005 so I'm not sure if this is still relevant.

Over past couple of years, I would get this pulsing noise and vibration (like a wu-wu-wu-wu) around 80-100 kph but nothing before or after the speed. This would happen occasionally. In past few months, it's been very present everytime I hit this speed range. I have brought it to dealership's attention but they can't seem to duplicate it. I personally don't think that they have taken it on highway to check it out as odometre # never changed. I know it's coming from front end and can feel it under my feet and sometimes seat but cannot pinpoint whether it's on left or right side.

Based on google search for similar problems, I'm pretty sure that it's the wheel bearings but I have no problems with my alignment. Tires change have not made a difference. Are there anything else I should look for before taking it back to dealership (i still have warranty on the car) with some possible problems on hand for them to look at?

Thanks in advance.

[Dynames]

Unless you are feeling it in the steering wheel its probably the rear though obviously it may be more complex to diagnose than that.

Did you check if you have a bent rim? Jack your car up and spin the tire to check. Uneven tire wear can also contribute also. Besides alignment did you check if your wheels are balanced? Just because a shop does your alignment doesn't mean they checked for balance.

[Kat]

No bent rims and this is happening no matter what kind of tires that I have on.

I did have my wheels checked for balance a few times by different shops and they were all fine.

[ottoyu34]

Any possibility to go on a test drive with a mechanic?

[studum]

That's what a bearing sounds like, a low pitched moan or groan that will vary with your speed.

Does it get worse when you turn one direction vs the other? That's a solid indication of a front bearing going bad. If you turn left and the sound get's worse it's the right side that's bad. Vice-versa for when you turn right and it gets louder, then it's the left side.

PS - you can still have your wheels balanced with a slightly bent rim or a shifted belt in the tire. When you switch tires and still hear it are you using the same rims?

Other test is to rotate your tires. Move the fronts to the rear and vice versa and see if it's the same or if noise / vibration has moved to rear.

[loki]

v-tech?

[drazen]

Wheel weights in the rims?

[Superchargedx]

Almost gaurantee it's a bearing or tires due to lack of rotation.
They get feathered and cupped on the inside tread if not rotated every 8k.