Got the howl at 1959 miles.........next steps

On Thursday night I finally heard the howl.

58-63 mph while backing off throttle. Not loud, but my ear is now trained to it.

On Friday morning, I did the following things:

1. Took it to an independent transmission shop - more on that in a bit.
2. Called Toyota care and got my case number - more on that in a bit.
3. Made an dealer appointment for Friday the 29th at 1PM.
4. I called our corporate lawyer. They are writing a letter that I will take with me on the 29th. Ac copy will also be sent to Toyota Corporate.

On (1) - We have a dedicated diesel shop near where I live that has done a lot of work for me over the last 13 years. They are a transmission specialist and built up 47/48/68 trannys on Cummins rams for more horsepower.

We did a drive along and then they put the truck up and put their stethoscope on it. At this point, they are not going to open it up. That may or may not happen later. That will depend on Toyota.

Immediately upon hearing the noise, their lead mechanic stated two things, first it does not happen under load. Second, he's about 99% sure it's pinion/improper backlash. There was a lot more technical stuff, but I'm not a differential specialist and do not want to muddy the waters so to speak. Until this is diagnosed definitively, this will be the last speculation about the issue that I post.

He stated that if that is the case - and after being told that Toyota does not have a fix - he recommended monitoring it. If it gets louder, start to worry. After chatting he said something that kinda took me back - it was along the lines of "I see a lot of trucks in here that make diff noise, almost all of the owners are completely oblivious to it." I asked him if it was a long term maintenance problem and he pointed out that the noise is usually indicative of improper set up, but that the degree of error may or may not lead to issues down the road - hence keeping and ear out for the noise getting worse or more widespread.

On (2) I spoke to rep at Toyota and received a case number. I told them that I was aware of the earlier TSB on the second gens and was also aware that our local dealership stated that the replacement diffs were just as noisy as the first. While they would not verify or deny what I was saying, they did note that they have been aware of a noisy diff issue for an undisclosed period of time.

I pointed out that their track record was uninspiring - issuing a TSB 9 years into a production cycle all but negates the possibility of earlier models getting a fix under warranty....as far as I was concerned, they had sold me truck with a potential long term maintenance problem - and they did so knowingly.

When I called the dealer to make an appointment, they confirmed that they were aware of a diff issue separate to the recall and that the repair precluded them from tearing down the diff....they had been instructed by Toyota to replace the entire third member based on verification of the noise.

As far as the legal aspect, if Toyota also diagnoses the issue and cannot repair it, we will begin documenting the fact that the vehicle has an uncorrectable defect that cannot be addressed. At that point - despite the fact that we love the truck - we will begin the lemon law process.

Once that process has begun I will consider whether or not I will have a tear down done on the diff. The legal advice I was given was to have it done as part of the assertion that there is a known issue that Toyota either cannot or will not address and that it will be evidence in the case. The tear down will be performed as part of the legal action to prove that there is an issue and to prove that it poses a manufacturing or engineering defect.

Having said all that, at this point, the noise does not bother me. If it gets worse, it probably will. My path at this point has been set by the fact that I know that Toyota has known they have a potential issue for over a decade and has done nothing about it.

Which leads me to my last point: having spoken to several people who work on diffs - including our own master mechanic - there is a possibility that I may not be able to prove that a defect exists. Our mechanic pointed out that he has an ear for these noises and his wife's 2008 accord has made a pinion whine since new and that he has never been able to find any signs of wear or that the gear set up was wrong - according to him everything is within Honda specs. He also pointed out that his wife does not "really hear" the whine.

So the next step is verifying the noise with my the dealer. I'm not going to update this until I have something to add to it. If anyone has any additional questions, PM me.

 

Want to know what the transmission shop told you.

 

mine makes the same noise and toyota told me it is normal behavior

 

"We didn't hear a noise." is what I got.

 

Excellent. I'm impressed with this post.

 

I just noticed mine for the first time feathering at around 57 mph. I have just under 2500 miles. It's very faint right now and unless it gets worse...I guess I don't care. This has been going on with Tacos for over a decade...has nothing to do with "turd" gens.

You took all the right steps. I'm going to do a similar step by step just to ensure there is official documentation in case it gets worse.

Good luck!

Edit: at some point, if we start actually seeing widespread failing and not just noises, I hope there is a class action lawsuit that TW folks take the lead on!

 

Mine has the howl too. Feathering on/off throttle anything over 45 gets a pretty good whine going.

If its like mine, it'll get much more noticeable over time. Dealership said they hear it and to come back at 20k and mention it if its worse.

Tech at my dealership and tech at another dealer have told myself and another guy who've been working this awhile that it is likely improper lashing due to the crush sleeves not being torqued evenly. Both of us have manuals, and are getting a clunking due to the slop it is causing.

The reality is that the tech you talked to is right. Most people don't notice it, and most of it is still within operating specs. Time will tell.

 

Do A/Ts howl or is this just a M/T problem?

 

Your last point from your buddy is key... a whine us not necessarily a defect. I have been driving a lot of vehicles for a long time and most have some drive train noise at some speed at some load. I would recommend the exact same... listen over time.

 

The folks I've talked to that hear a noticeable whine are mostly MT owners. There are a lot of recorded AT owners saying they have it though - but MT owners are working through the clunking that we think is a secondary symptom of improper lashing. Honestly, we're not getting very far with sorting it as there just aren't enough miles on these things to get to where its out of spec yet.

 

Interesting. Thanks for answering. Guess I should have asked at the official thread that has like 150 pages!

 

I would be more worried if the noise were at load and louder as speed increased, not when you were feathering the throttle at a specific speed and frequency.

 

Yeah same. It could be tooth profile at certain rpm, harmonic developed through case, backlash maybe but that usually gives you noise in many conditions, not just a narrow band of speed. It could be a lot of things but is it a problem is the issue. A constant howl is one thing. A slight whine for a second when letting off throttle is something else.

 

This is the biggest crap statement they will give you.

They said that about the fuel pump on the FR-S (the cricket noises) only to have a TSB put out months later.

"this is normal" = We have no F@$%&#@ idea, sorry" lol

 

Normal or typical?

I'll worry when they start exploding due to the whine, not because of lockup due to fluid leaking out from improperly torqued hardware.

 

In fairness, frs and taco hpfp aren't failing and are operating within specs and noise tolerances. Mine chirps time to time. It's annoying but seems to be fuel and temperature related.

More noise on winter mix fuels and less during the summer.