Mine has had this noise since I bought it with 3 miles on the odo. Granted, mine is much less pronounced. I only hear it at higher RPMs such as when I’m on an on ramp.
18 TRD ORP.
I’m not concerned about it but it is a little annoying. The 1GR is not a quiet engine.

115K on a 2012, mine does it. It's gotta be normal. Too many do it. I dont hear about engine failures. Just drive it.

I read this diagnosis on another forum but don't know if it's correct.

"I noticed the same noise with my '19, and was speaking with the head tech at my dealer. Evidently there is an air pump that pumps air into the engine, and this is what we are hearing and it is normal. It is the same noise you hear when turning off the vehicle, of the system purging. I was starting to worry that something was wrong too, but this is done as a part of the whole ECO process that everyone is jumping on now... I hope this helps..."

I understand that this is the 5th Gen T4R section. Mine is 4th generation 2008 4Runner Urban Runner with exact same noise as shown in the Youtube video in this post. Hope this helps some of you out there.

Three Parts were replaced by my Mechanic and the problem is fixed. I think Tensioner Pulley and the Bearing is what has fixed the problem. He might have replaced the Drive Belt based on the condition of the belt.

Replaced parts:
1. Tensioner Pulley
2. Bearing
3. Drive Belt

I have the noise on a recently purchased 2015 SR5, and it’s a little annoying. I didn’t notice it when test driving the truck. I picked up the noise after cruising it down the interstate, and now I notice it at low speeds too. Is the consensus that it’s definitely not the transmission? I notice it in drive or neutral getting louder with higher revs.

Would love some sort of definitive explanation from the dealers and techs.

I doubt that have any clue. It doesn't cause any problems... there are no threads about anything failing from this, so it's no big deal IMO. And yes, I have the whine. Dare I say I kinda like it...

So I bought this 2014 Toyota 4runner with 98k miles on it. We had went 2 hours away to a small dealership and found this one for 24,800.00 so we snatched it up in a heartbeat. It has 4wheel drive and everything she test drove it and said she loved it and signed all the paper. Was sold as is. When I get home I hear this and I literally shat myself. From what I deduced after reading all of these articles is possibly oil filter is garbage and possibly oil pump is bad or is this common. It sounds like a loud supercharger.


YouTube

So I bought this 2014 Toyota 4runner with 98k miles on it. We had went 2 hours away to a small dealership and found this one for 24,800.00 so we snatched it up in a heartbeat. It has 4wheel drive and everything she test drove it and said she loved it and signed all the paper. Was sold as is. When I get home I hear this and I literally shat myself. From what I deduced after reading all of these articles is possibly oil filter is garbage and possibly oil pump is bad or is this common. It sounds like a loud supercharger.


YouTube

I have the same noise on my 2016 with 38k miles and I had the same concerns when I noticed the noise and found this thread. If it makes you feel any better, I’ve heard it on brand new 4Runners. That knowledge and the varied years/mileage that people notice the noise gives me some confidence that it’s nothing to worry about. I never had it on my many other Toyota’s, but the accessories on this engine for emissions control make strange noises on shutoff and it sure seems related. Congrats on the new rig.

I purchased my 5th gen SR5 with 39K on it back in December 2017. Last spring (May 2019) at 58K, I started the truck up in the garage and heard the whine at 1000 RPM and up out of no where. The day (weeks, months and years) before the noise was not present. I have an extended warranty on the truck so I asked the dealer to take a look at at my next oil change (only about 600 miles later). They tested the alternator output (normal), compared it to another same model on their lot and chalked it up to normal noise. Based on all that I've read on this thread and another similar thread, I decided to let it be and not worry.

Fast forward to my next oil change (just a month ago at 67K). For kicks, I went to a different local Toyota dealer to see what they had to say. They bit on the extended warranty work right away. They verified that they heard the whine and seemingly willy-nilly replaced the alternator as the "fix". Again, based on what I've read, I had a very strong feeling that this was not going to be the fix but was happy to take a new alternator anyway. They gave me the truck back claiming noise was gone, but, of course it was still there.

Fast forward to today (March 6 2020 at 67800 miles) when I was able to get the truck back in and verify the noise with the tech and service advisor. They heard the noise with me. I explained that via this forum, it seems they should remove the belts to isolate the issue. They did this and the noise was still present. They've now decided to order an oil pump for the truck under warranty. I expect to bring it back in for the swap late next week. There's been a few guys on this thread that have had the oil pump replaced and that seems to have fixed the issue. I'll post after the work is done and confirm if it fixed mine or not.

As always, thanks to y'all for taking the time to share.

Looking forward to hearing how the above fix goes. I've gotten used to it at this point, but I welcome any solution if there is one.

FWIW - mine has made this sound for quite some time. No adverse effects. It's not particularly noisy, but I can here it under moderate acceleration. Not planning on doing anything. Doesn't bother me and doesn't seem to indicate any sort of failure.

Mine has the same noise, I was thinking it was a pulley or maybe the belt. I have a 127k on the original parts, was going to replace them both at 150k. I'll re-post if the noise goes away or gets quieter.

Hi,

Just wondering if the oil pump replacement ended up fixing the whine?

My 2016 Trail edition just started making a whine this morning.

Making this exact same sound YouTube

Maybe all you Karens should voice your complaints to corporate regarding this noise with no known failures.

Perhaps a strongly worded letter on how difficult it is to co-exist with such an intolerable racket under the hood?

I'm sure they will be very receptive to your concern.

lololol