Howling just started today

Never had any noises until my ride home today. I started hearing a faint humming and I immediately thought "oh no...not this". Truck has 11,400kms. I watched some YouTube videos and this noise is pretty much exactly what I hear at similar speeds:



I did some research and noticed there were two TSBs applicable. One invoking plugs in the the holes on the front CV mounts and the other installing a sound dampening kit in the back of the cab. The CV TSB seems easy and noninvasive but I don't want the dealer ripping apart the back-seats for something that isn't a real fix.

Looking into several threads it seems people have had these TSBs applied and even had their differential replaced and the noise has either gotten louder or has come back and apparently Toyota considers this a normal characteristic now?

Can someone give me a skinny on where we stand on diff howling in 2019? Is it normal? Is it a sign of diff failure? Will I explode on the highway? Should I just apply the "buy loud AT tires" tacomaworld TSB and forget about it?

 

its rear end harmonics.
I had the TSB done which includes new rear leaf springs. Didnt fully eliminate it but but reduced it to where I cant hear over the radio now and I keep my radio volume relatively low.

 

If it ain’t broke don’t F with it

 

You may have ended up with a TRD Smitty edition.

 

I see. Harmonics I can live with, I just want gauge whether I need to ditch at lease-end or whether it's probably safe to buyout. I'm curious though why Toyota has replaced so many diffs if it's just harmonics? Were they just throwing diffs around in a panic until they understood the issue better?

This is my attitude as well. Nothing is ever quite the same when dealer techs rip everything apart and put it back together. I want to avoid unnecessary work if this is nothing to lose sleep over.

 

please stop. I don't want this thread to be derailed into a Clint Eastwood meme shitshow.

 

Mine is louder than yours. At 62 mph it just pisses me off.....
So if it is harmonics??….Why was my truck almost silent for 7k miles.
My dealer says there is nothing wrong, normal operation.

 

Exactly!! I couldn’t tell you if mine howls or not but I do have A/T tires and usually have music on. If I do end up noticing it I have no plans to do anything about it

 

monitor this and see how much it bothers you, if you don't forget about it dump it at lease end, at least you have the option. i picked up my 2018 in kanata and had my last one serviced there, from my dealing wth the service manager he was willing throw parts at my truck until toyota said stop.

 

Put 35s super swampers on it and you wont hear the howl anymore, or anything at all for that matter.

 

I was more thinking c load KO2s...might not be loud enough I guess.

I have tried to find this issue leading to actual differential problems but haven't found anything. Just regular 4WD diff mishaps or other driver-related failures.

 

The wobble from your KO2s will probably be enough to distract from your diff howl

 

Wow, that sounded totally normal to me. Is that the howl I’ve read about for 2 years and never thought I had?

 

FWIW, mine was silent for the first 1000 miles. I also had the TSB yet it kept getting worse. Toyota just replaced my rear diff and confirmed it was bad. Most are probably ok but some apparently are not. We have a thread on this as an FYI. Best of luck to you.

 

The noise is not a sign of failure and has no effect on the longevity of the diff. Is it normal? I'd say yes to some degree. I have a small amount of it. My last 2 Toyotas had it (Highlander and RAV4). As vehicles have gotten quieter in the cabin, this problem has become worse because you can hear it clearer.

 

I see. Good news I suppose. It's only alarming because I never noticed it until now which make it seem like mechanical wear and tear.

I might have my dealer try the sound-deadening TSB but I shudder to think they'll make the cabin noisier with rattling as a result.

 

Mine started at 0 miles now 78k and still makes it. All the tsbs are up to date. The leafs made it better. We will see what the Dakars do for the noise. Toyota granted me a 100k warranty

 

Mine does this from time to time... usually on the tail end of a long drive... I generally just turn my music on louder by this point...

 

I don't know the root cause for the Taco, but in the case of the Highlander and RAV4 (both of which required a transmission replacement to fix), it was the final gear assembly. Apparently, if the final gears are not honed correctly, it would cause the issue. Interestingly, after the transmission was replaced in our Highlander, the noise came back after 75K miles.

 

jesus, transmission replacement for both? Are we still talking about Toyotas here?