Rear Differential Howl

Okay. Reading a lot on here about a common problem of Rear End howl.
The truck that we are looking at has less than 15,000 and I will test drive it before final decision to purchase. If I detect the howl while feathering the throttle, how do I address the problem with the dealership and get the truck fixed???

 

Depending on the year, and model truck there is a TSB that addresses it, its is a resonating issue where the diff transmits sound up into the cab, they will put some more sound deadening material in the cab and a few other things. It may or may not solve the issue. I have had it on my 2016 and 2020 TRD OR.

 

If it is that bothersome on the test drive I would suggest not buying the truck, the TSB may not fix it to your satisfaction.

 

It’s a truck. It makes noises more than unibody cars. Especially tacoma.

 

Yeah it's a truck.. but I've owned/driven a lot of other trucks and RWD cars that didn't do this (unless they had an actual issue) If everyone just rolled over and said, yeah that's normal for a Tacoma, nothing would ever get addressed. See the list of TSBs for the 3rd gen.

OP, I had an early production '16 Access Cab OR that howled quite loudly, and now have a '19 Double Cab Sport that howls, but is hardly noticeable. Zero mechanical issues with either as far as the rear axle is concerned.
They don't all do it, some are worse than others, but Toyota has attempted to deal with this annoyance.

 

https://youtu.be/b6tRAQ_r0Ms

Check out this video. I found it interesting and aligned well with My experience and what I see on TW. These are inherently noisy vehicles.

 

It's funny, that exact video was linked in another thread recently, and some TW gaslighters immediately dismissed it as "some guy on YouTube " lol.
It's actually quite accurate IMO, although he didn't mention the Crank Position Sensor/fuel pump recalls and the manual trans detent TSB (shifter sticks in gear after driving for extended periods).

 

Has anyone heard of a 'Taco diff grenading due to the howling? I haven't.

 

The problem with videos like that is the framing of the issue. If he qualified the potential problem up front by saying... "Some people have had this problem" or "You may or may not have this problem" then it would be fine. Also, keep personal opinions out of it. He can speak as a tech. He cannot speak as an engineer, designer, marketing expert, etc just like I cannot speak about accounting or crane operating.
For example, he talks about the frame difference being only a little triangular piece added from previous versions. In reality, the frame has much more HSLA and UHSLA material than previous versions, which makes it much stiffer, and is documented by Toyota.
Basically take it with a grain of salt, not treat it as gospel, but many people do.

 

Nope.. a few could have due to the leaking problem they had for a while there.. dunno.

 

It won't because of the noise because it's harmonics making the noise at a specific frequency generated at a specific speed. Only hurts the ears.

 

I'll take the word of a Toyota master tech who sees a shit ton a vehicles over gaslighting TW superfans any day.. some ppl will JUST NOT acknowledge that this truck has had it's share of issues (like all vehicles do).

 

And when enough ppl didn't like it, Toyota came up with a "fix" to tamp down that noise. I mean, the guy hit the nail on the head when he said these trucks aren't smooth and make noises. Just is what it is.

 

I have had this problem since I got my Taco and I've been told that my Taco already came with the parts for the TSB installed. In the end it is just a harmonics issue, because it happens at a specific speed usually 55-57mph. At that speed vibration occurs which as people said transfers to the cab. There's multiple threads with people taking it in to the dealership to get the issue addressed. Some have had the whole rear end taken apart and everything replaced brand new to still get the howl reappear.

In the end it is not damaging your truck, it's just a minor annoyance (though that depends on your annoyance threshold). For me, the wind noise from my roof rack plus rocking out some good 80s rock prevents me from hearing any noise. It's a truck and it's going to have truck noises. FWIW many people have said the howl goes away when the truck is lifted.

 

Good post.. when I had my '16, the singing of Duratracs and 80's rock drowned it out lol
FWIW, the annoyance level was moderate for me, but everyone who rode in my truck inevitably had that look.. WTF was that?

 

Don't know if a coincidence but, since my buddy sprayed his entire trd chassis underneath with cosmoline he hasn't noticed his truck howling anymore. Vibrations are still there, but he's happy to be rid of the howling.

 

Toyota appears to have taken the issue seriously on the Hiace. The 8.8" axle receives a damper.

 

That had to be messy,!
Definitely a good corrosion inhibitor.

 

What vehicle has this Damper?
I assume it's that shackle looking thing on top of the 3rd member?

 

Foreign market 2019+ Hiace Vans. This is the 8.8" manual transmission axle. Automatic Tacos will have 8", and I have not looked into that.

Yes, on the 3rd.