I have a 2002 Honda Odyssey. I was driving on a longer trip last week and started to hear a whistling sound while on the highway. It was only when I was going around 75-80 mph, when I slowed back down to 65-70 the noise seemed to go away. The noise sounded like someone was blowing over a coke bottle…it was also a little intermittent - it would come and go.
I would check the roof rack if you have one. It a low frequency sound like blowing over a the opening of a bottle might be a loose cross member. If that isn’t it, check the doors and windows to make sure they are all closed and the rubber seals are intact. Next, I would look for something loose in the engine compartment and wheel wells. Check for loose pieces of plastic under the front of the vehicle too.
Thanks - I’ll check those. I just took it into my mechanic and they didn’t find anything under the hood, nor could they replicate the noise when they took it for a drive. But something loose on the outside of the car, or a loose window seal would make sense. Thanks for the advice!!