Faint Helicopter Noise / Possible Wheel Bearing Replacement?

Faint Helicopter Noise / Possible Wheel Bearing Replacement?

Hi All,

I have a 2015 Model S with 104K total miles on it. RWD with 85KWH battery and staggered 21" Pilot SS tires on arachnid wheels. Recently I'm noticing a kind of faint "helicopter" like sound, especially when cruising at low speed. I took it in for service recently and the team just quickly looked it over and said everything seems fine but the noise persists. I have new rear tires that I got recently. Fronts still have some meat on them.

- Has anyone observed a similar noise with their vehicle?
- Has anyone had to replace their wheel bearings and if so when?
- Any tips on how to tell if the noise may be tire related, wheel bearing, or something else?

Al | 30/01/2020

One thing to check is if one of your tires has a bolt or nail that has embedded into the tread. Sometimes even a small rock can wedge into the tread and make such a noise.

GHammer | 30/01/2020

I had the same exact thing happen to me on my staggered setup after i replaced only rear tires. I thought i had a noisy wheel bearing as well and a service center tech did a test ride with me and he agreed thats what it sounded like but apparently its extremely rare for a bad wheel bearing in a Tesla. They found some slight scalopping on the inside edge of the tires even though the rest of the tire had about 5/32. New front tires and an alignment and it was taken care of.

GoldAK47 | 30/01/2020

Does it sound like a car with window down and wind pulsating? Like mild pulsating bass?

Or more like metallic?

GTM | 30/01/2020

The frequency of wheel bearing noise will increase with road speed, not stay constant, and is usually not present at lower speeds (typically absent below 30 mph unless the wheel bearing is totally fubar. And any decent tech would hear that). Wheel bearings also react to changes in load. A right turn lightens the load on the right side and a failing right side wheel bearing will usually quiet down. If you are not noticing any change in volume with changing side load then it is probably not a wheel bearing. If the noise is still present with no torque on the drivetrain (coasting in neutral/0 Kw usage on a hill) then tires are the most likely source.

Techguy817 | 31/01/2020

Thanks all for the replies. Appreciate it.

It sounds like a wind pulsating noise.

Brought it by service again and had another tech listen to it. He doesn't think it's the wheel bearing or drive unit. Likely an issue with a tire so they'll inspect and re-balance them all and then see what happens.

Bighorn | 31/01/2020

If there’s a wheel out if balance, it could be the trunk lid pulsing.

Bighorn | 31/01/2020

Out of | 31/01/2020

@Techguy817 - BH reminded me, if it only happens with a window open, the trunk lid if not adjusted correctly, it will create a low-frequency thumping as the trunk vibrates slightly up and down. My guess the tech is aware of this issue, and would have known if that was the issue or not.

Bighorn | 31/01/2020

It can happen with the windows closed if the balance is off far enough.