What is the sound i'm hearing when slowing to a stop?

Maybe it's normal but just thought i'd ask here ...
I have a 16' SR5 4x4 with the 2.7 and notice (with radio off) when i slow to a stop i can here a sound that slows as i slow down like its the drive shaft turning or ? hard to explain .. not super loud but i can hear in the cab whoopwhoopwhoop whoop whoop ----- whoop ----- whoop --------- whoop ----------- whoop -------------- whoop -------------- whooop -----------------! whooooop it slows and stops as i slow down. Has to be something that rotates hince why i was asking if it may be the drive shaft turning
i did grease all 5 zerk fittings when my truck had about 5k miles (7k now)

Thanks for any feedback

 

Anyone? could it be a wheel bearing? going to take it in and have it checked as it don't sound normal to me

 

Are you on the original tires

 

Subbed because I have the exact same sound.

I only noticed it when it got cooler in the mornings but it's definitely a rotational noise exactly as OP described. Once I've gotten about 5 minutes into my commute it's gone. My truck is bone stock minus a softtopper and the A/C drain hose. My best guess is that the transfer case fluid is viscous enough in the cold to spin the front driveshaft a bit even though I'm in 2wd (based on nothing but my gut feeling). I can say this didn't happen in the 4Runner (limited) that had a center diff and full time 4wd.

Edit: I greased all 5 zerks when I had about 1000 miles on the truck. I just greased them again yesterday (aproximately 6500 miles now) while I was under there spraying myself and everything underneath the truck with fluid film. Will update after my next drive whether or not the noise went away.

OA

 

Yes everything is factory, i have the P245/75R16 Hankook DynaPro tires ... i only notice the noise when slowing to a stop, its a rotational noise as the noise slows as my truck slows

 

It's your truck lifted?

 

No everything is stock

 

The Tacomas have some "mechanical gear" feed back as I call it through the drivetrain. If your lifted it could be the front differential driver side needle bearing. I already replaced mine with the ECGS bushing and my growl is now gone.

 

Coast to a stop vs. braking to determine if it's the brakes..... My thought is that it's probably the tires though.

 

Yes i tried that ... i can still hear it when i coast to a stop. What would it be with the tires .. out of balance or ?

 

Not lifted

 

Does the sound go away if you put into 4wd?

 

Noticed the same thing in my 2.7 5mt, even happens in neutral.

Definitely a cold weather thing.

 

Have not tried that yet but will try and report back

 

I had a similar issue with my truck. Actually heard during test drive, but it went away after a few minutes. Assumed it was a stone in the tire. It came back on cold mornings and would last several miles. Sounded like a light clicking noise. Mine actually got worse in four wheel drive. 2017 TRD Sport, fresh off the lot brand new. Needless to say, I was not to impressed. This is my first Toyota, previously owning several Nissans.

In the end it turned out to be a simple issue, but could have been more serious had I let it go. The front drive shaft was clipping the transmission control cable. Apparently, there is less than 1/2 inch clearance from the factory. Simple fix, but I can see that this issue might be out there on more trucks and if left uncorrected it will permentatly damage the shift control cable.

My dealer was awesome and got me a new cable installed and confirmed clearance. All is good now. I am not sure if I am alone with this, but felt it worth posting to the forum.

Otherwise, I love the truck and very pleased with the speedy correction by my dealer.

Pics from under truck:

 

Hey OhioTaco, I think I have

 

Dust shield contacting a rotor?

 

Hey OhioTaco, I think I have the sound you have on my 17' as well. I hear it from different locations slowing down. At one speed it will come from the left rear. As I get slower, the front left, had the master tech at my dealer check it out. He says its normal harmonic sounds from the drivetrain. Some experience it more than others depending on how "snug" the truck is built. If I'm driving at exactly 12 mph I can hear it constantly from my left front. 11 mph and below nothing. 13 mph and above nothing. Seems logical, I have 4200 miles and it has done it since I got it.

 

i don't know when you got your truck but if its a 16 it would seem to soon to be a wheel bearing , i would think tires as well off balance or alignment ?
any wear on just the outer edge of the front tires ? hit any good pot holes lately ?

 

If you have trouble determining the location of the sound and it sounds like it comes from a different location on the truck, that's a symptom of a bad carrier bearing.