3rd Gen Poll: Rear End Noise howling when feathering throttle

https://www.tacomaworld.com/threads/solved-howling-noise-between-35-45.410480/page-20#post-14950268

 

Here is how my Truck looks Plugged from the Factory.

 

And my guess is this is unrelated to the rear end howl? I don't hear any howling from the front and all my holes are open.

 

Exactly, 2 totally different things.

 

I hear the same audible "howl" y'all are talking about when decelerating from around 65-ish. I'm not saying the sound is not the diff, but this doesn't sound like a differential issue. I think it is a Helmholtz resonation sound created by the force of displaced air flowing at angle over an open cavity somewhere on the truck. I know Toyota has formally plugged some open cavities already, but it seems there is another one or more.

The proper diagnosis in the spirit of leaving no stone unturned is to apply duct tape over every open cavity throughout the vehicle. I am not volunteering; I'm just sayin'!

 

My howl isn’t strictly on deceleration.

I like your thinking. You go first


Also a lot of us had the howl diagnosed as a bad pinion bearing. They could replicate the sound with the truck on a rack.

Im pretty sure it’s drivetrain related

 

The noise only occurs when the drive Train is under load, and it persists for a half second after being unloaded.

 

Well I am happy to report that the rear diff. swap worked for me! I guess I'm one of the lucky ones. Now all I need is to get Toyota to fix the vibration issue between 2-2.5k RPMs and I'm set. If it will help with the battle of the dealers, I'm more than happy to scan my invoice(s) and upload. Maybe they can be used as ammo for the dealers who don't want to acknowledged/fix the issue?

 

Yup but its staying together.

We will see when I start towing things

 

How many miles have you put on your new diff?

 

2016nTSS new diff.

2017 just a seal but I have not done any towing we shall see.

 

As of this morning, about 100mi.

 

Keep us updated as the miles stack on---most diffs don't start to howl until a few hundred miles...mine didn't make a peep until about 5 or 600miles on it

Not sure how promising it'll be since even the 2018s are getting report with howling diffs so it doesn't seem toyota has really done anything differently. I'm surprised they are still replacing them at this point.

 

I cannot get them to do anything except change my oil and rotate my tires at the dealership. I've had the howl at 50-55 MPH on two 17 TRD 4x4 DCLB's. I know it has do with the bad gear setup from the factory. I think i've taken my truck to the dealership at least x5 times for the differential howl. I know there is a " gag order" or " black list" on my truck via the vin

In addition to that, I also have the yoke slip or the " clunk". I've tried to do trade it in. I owe more than its worth.. So I'm stuck at the moment. Seriously, Toyota is committing fraud in my opinion. At the very least breach of contract in terms of warranty.

Lemon law attorneys have looked at my case, it's hard to get them to take on my case when no parts have been replaced. Toyota's tactic is to just say " normal characteristic". Thats how they avoid buying back our vehicles.

 

I would respectfully say that if LL attorneys have turned you away because parts have not been replaced then you have been talking with the wrong LL attorneys. Then again, there are not a lot of true LL attorneys out there. You can LL your truck yourself without an attorney. Read up on some of the things Steve Lehto has written on the subject. I don’t agree with everything he says but when it comes to the nuts and bolts of the LL process he is generally spot on. Also, read your state’s LL very carefully and just follow the procedures set forth in the law and do it yourself.

Once you start the official process Toyota will be much more willing to talk. They don’t want anything they make to be marked as a Lemon so they will likely get serious about a buyback or trade assist. As of now and without you (or anyone else, to include me) initiating any action against them, they view you (and anyone else) as a nuisance at best. I am starting the process of trying to get mine fixed after the first of the year. My wife is mostly healed up from her surgeries so I can now juggle my personal case with my work caseload. I really like my truck but if they cannot fix mine then I have a decision to make. I will likely just get rid of it or deal with it until I find something else I want. It would be my luck that whatever they gave me would be just as bad or worse. I LL’d my Yukon XL last year and got a great one but these 3rd gen Tacos seem to have a high likelihood of having this issue so I’m not so sure.

Best of luck to you.

 

Update on my 2018 dclb Sport. 500 miles and there are some slight harmonic noises occasionally from rear. Only reason that I even hear these is I’m being overly sensitive to it.

It does have the momentary harmonic sound if you are going 55ish and abruptly let off the throttle quickly. So far nothing anywhere near the persistent whine on my 2016 that started at 55 and never really went away.

Very cautiously optimistic but won’t consider it permanent until over 1000 miles

 

I have a 2018 SR5 that starts right at 60mph and makes noise until 54mph. I have to be completely off the throttle to get it to howl though. If I feather the throttle it goes away. I currently have 215miles on it and I first noticed it at around 20 miles. I’ll be making an appointment for it this week.

 

Hope you dodge a bullet