Strange whistling noise when moving

Trying to find the cause of this, any help is appreciated. This whistling noise recently started a couple of weeks ago. It happens only when moving, when I press and not pressing the brakes, at different speeds (low whistle when going slow and a high-pitched whistle when going fast).

I recently did the following
-Installed stubby bumper
-Changed brake pads
-Cleaned throttle body

I've checked the brake pads and nothing seems to be rubbing, I've checked the hosing to make sure the throttle body is on properly. Maybe the whistling is coming from the bumper? It has a bunch of holes in it and I haven't installed the winch yet...

It only happens when moving, I've revved my vehicle and kept it at multiple points of the RPM meter, but couldn't replicate the whistling noise when at a stand still. This leads me to believe it's something on a moving part. I'm about to have my brakes checked again, just for ease of mind.



Edit - I'll toss $70 to anyone that can help me figure out what's causing this!

 

Wind noise maybe from new bumper?

 

I’m hoping that could be it. I just got my winch in a few days ago and I’m waiting on 650lbs springs to come in to accommodate the extra weight and the sag I already have.

 

Is it that metallic sound? It’s hard to hear completely with the exhaust. I’ve seen where the brake pad wear indicator was pushed forward on new brake pads and was prematurely contacting the rotor but I feel like that is a more obvious noise.

 

I did check the wear indicators and pulled them back a little, but that didn’t seem to fix the issue.

An update, replaced the stubby bumper with a full Lil B bumper and winch, noise persisted.

Reseated throttle body multiple times, noise did not change at all.

Installed new rotors and pads all around, noise did not change.

At this point I’m losing my mind . I’ll give anyone $50 if they have any theories and it ends up fixing it. I’m about ready to pay a diagnostics fee to have someone look at it, but that’s around $100-120.

 

When I was in high school (back in the dinosaur age) and whistles came free in some boxes of cereal, I glued one in the tailpipe of a friends car at school. It whistled for about a day before the heat melted the glue and it blew out. He never did figure out what it was.

 

May sound ridiculous, but I had a somewhat similar experience; found that the window weather stripping on the top of the driver side door had not been properly seated after having the windows tinted. It was down just enough to not be readily noticeable (even with the window up), but enough to allow a bit of air/wind noise through causing a slight whistle. May be worth a look.


Pic for reference.

 

I've noticed this sound as well. I figured it was the wind between the side view mirror and the A pillar on the outside. If you put your had in that space when you hear the noise the noise stops. I came to the conclusion that it's simply the aerodynamics of the shape of the vehicle. You can try something like this but haven't tried looking for one for a 4Runner...I've just learned to live with it.

https://www.armaspeed.com/product/toyota-supra-a90-armaspeed-windblock-side-mirror-kit/

 

Entire front end was replaced after an accident.

Checked weather stripping, seated properly

Did this, noise persisted with my hand in that area.

 

What about putting it up on stable Jack stands and then running it in drive with someone on the outside listening ?

 

I had similar noise from underneath the front. I put masking tape on the holes on the lower control arm and it disappeared. I found out that in certain conditions and wind direction it worked like a flute. Since then I sprayed some Waxoyl there and the noise disappeared plus well protected against corrosion. Try masking tape on the commonly known areas and remove them one by one to locate the origin of the noise.

 

I suggest blue painters tape 1-1/2" (better removal than beige masking tape). Try taping around windows/door frame to make air seal on one window - then test drive. If sound still there - add tape same window door frame to body. Test drive and so on till all windows and doors tested.
Do not leave vehicle in sun with tape on! Remove all tape same day!
Have you tried taking windshield wipers off then test drive?
Have you added crossbars to roof rack?

 

When replacing pads did you get the springs correctly positioned? Are you using factory pads? Did you bed in the new pads? Did you put the special brake grease in the correct places? Pins and between steel shim and pad steel plate?

 

I hooked my phone to my surround sound Home Theater amp & speakers and listened to your youtube carefully.
I hear a ringing tone that has a metallic note to me. It seems familiar to brake rotor/pad sounds I had with my Pilot years ago. I did not hear the whistling wind noise I experienced with my 4runner when I lashed an awning on my roof rack one time.
What are the surfaces of your brake rotors like? If you lightly press brake when noise is ringing-does it change?

This about exhausts my thoughts on your annoying problem. Hope you solve it easily.

 

I also have this issue on my 23. It’s driving me crazy not being able to resolve it. It started around 4k miles if I had to guess.

 

Were the lower control arms replaced as part of the repair? On the Tacoma for example, the anti-whistle plastic plugs are not included on replacement arms; Toyota makes you buy them separately.

Is the gap between hood and grille surround larger after repair?

 

I’d have to find someone that has multiple jacks or a lift. Or I’d have to buy a few more jack stands.

Just tested the LCA, taped up the holes but the noise still persists.

I did the brake pads myself, then had the rotors and pads done by a professional, didn’t change the noise.

Noise doesn’t change with pressing of the brake. Rotors look new and don’t look like anything is dragging or rubbing.

I did try the LCA holes, but that did not solve the issue. They were not replaced after the accident and the noise has been an issue since before.
Hood and grille don’t seem to be the issue

 

Took it to a shop, they had it for half a day and they couldn't figure it out. Upping the bounty to $70 (Cashapp/PP)

 

I sounds pretty damn consistent to be mechanical.

Try turning off all the electronics in the 4R. Radio, AC/Fan even DRL if you got.

*edit
I listened again and are we talking the constant high pitched noise you can hear from the system. The only other one I hear after you step on the gas. Kind of can hear like wind noise around 13 sec.

 

Is the weather stripping torn? I started getting an air-raid type whistling last week after the temps took a dive. Seems the whistling has to have temps in the mid 30's going 60-75 mph. I thought the X-bars were the cause, but they have been on for 3 years without issue. I recently tore the weather stripping on the rear pass. door getting the grandsons car seat in. I'll have to do some digging to determine if that my be the cause.

 

Alex, I’ll take deer whistles for $70.

https://www.amazon.com/Elook-Warnin...4&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY

 

Remove your engine splash guards and give her a go.

 

Hmmmm I had a strange noise too.....

 

Tape phone to just behind new bumper with blue painters tape, record video while driving. If it's substantially louder it's the bumper.