Tire resonance?

[Versatile68]

My 21'' tires were overinflated at purchase. I noticed a fairly pronounced 25-30Hz noise around 30-35mph. Set correct pressure and now it is barely there. Anyone else noticed these buffeting noises that seems to be due to tire resonance?

 

[snesbit]

My 21'' tires were overinflated at purchase. I noticed a fairly pronounced 25-30Hz noise around 30-35mph. Set correct pressure and now it is barely there. Anyone else noticed these buffeting noises that seems to be due to tire resonance?

What is the correct psi for 3.5 Sport prestige 21”?

 

[Lionorion]

What is the correct psi for 3.5 Sport prestige 21”?

If you open the drivers side door, there’s a sticker on the lower B pillar just below the VIN sticker that specifies your recommended air pressure.

 

[Versatile68]

My 21'' tires were overinflated at purchase. I noticed a fairly pronounced 25-30Hz noise around 30-35mph. Set correct pressure and now it is barely there. Anyone else noticed these buffeting noises that seems to be due to tire resonance?

From the silence, it looks like I was the only one experiencing it. So, here is an update for future reference.
Two things contributed to the buffeting sound and air pressure fluctuations: overinflated tires and liftgate rubber bumper settings. With bouncy tires and uneven bumpers, the lifgtgate sometimes acted as a huge speaker. Apparently, Teslas and some other cars have similar problems.
Adjusting tire pressure and rubber bumpers fixed the issue.

 

[GV70GUY]

interesting.......

 

[DDN]

From the silence, it looks like I was the only one experiencing it. So, here is an update for future reference.
Two things contributed to the buffeting sound and air pressure fluctuations: overinflated tires and liftgate rubber bumper settings. With bouncy tires and uneven bumpers, the lifgtgate sometimes acted as a huge speaker. Apparently, Teslas and some other cars have similar problems.
Adjusting tire pressure and rubber bumpers fixed the issue.

Exactly what were you final adjustments of rubber bumpers that worked best? Are all 4 bumper lengths extended to the max?

 

[Versatile68]

Exactly what were you final adjustments of rubber bumpers that worked best? Are all 4 bumper lengths extended to the max?

My liftgate has two adjustable rubber bumpers. I used the "envelope method" shown in this video to adjust them. I ended up with fully in on the right and one turn extended on the left (driver side).

The hood does have four rubber bumpers and it vibrates too at high speeds/crosswinds, but I do not hear it making any noise. I played around with bumper adjustments but was not able to fix the vibrations. It seems to be minimized by extending all 4 to the max, at the expense of some misaligned/raised hood edge. My guess it is due to the lightness of the aluminum hood. I would be interested to hear about a fix.