2017~2024 2019 Signature - New Transmission Inbound

Hi everyone, just wanted to pass this along for info.

We've had our 2019 Signature since September and it's been largely flawless. Up until Black Friday, when we added a second vehicle to our stable (2019 30th Anniversary Miata) it was my daily down to work, a 132ish mile round-trip each day. We passed 10,000 miles on it a week and a half ago and had it's second oil change/inspection (2,800 miles were from a cross country move). Over the last little bit it had developed what I can only describe as a humming noise. It was distinct from engine and road noise and changed a little in volume but mostly in pitch with speed. I thought it might be a wheel bearing, which would be a quick and easy fix but a necessary one. I am not sure when it started, since it's not able to be heard with the radio on at my preferred volume, but driving with my wife I had noticed it and after doing some reading decided to get it checked out, which happened this morning.

So after spending some time at the dealership the diagnosis was a faulty bearing in the transmission (I am not sure which; I'm sure there are several). After providing me a loaner vehicle and a consultation with the Mazda mothership, the decision was made to ship a new transmission from Japan to replace the existing one (unfortunately not overnight like in the Fast and the Furious lol). So they're hoping to have it back to us within about 10 days. I'm happy the situation wasn't a "cannot duplicate customer concern" but am a little shocked at needing a replacement transmission.

It's never towed (doesn't have a hitch) and it's never been offroaded or driven aggressively or anything, it's just our family hauler. Only real bummer is we can't take our pupper to the dog park for a couple of days, but given the rain the past two days and the rain later this week it's likely to be a mud pit anyway.

I'll update if I learn anything further and once we get it back.

EDIT
Here's a link to video that I took of the sound - this was starting at 25 MPH on the way up to 45 MPH and then coasting down to a stop, from the driver's seat (basically held the phone with my leg). Video isn't the important thing, just the sound.

 
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I definitely hear that, sort of a whine. The transmission in mine (2016) went at 700 miles. See user name. Was told it was the Sport mode switch so totally different issue. Mazda may give you a call and offer you something for your trouble. I got a payment and extra warranty added. Took a little over 3 weeks to get mine back. Waiting for the transmission to ship took up most of the time.
 
There's a TSB that may or may not be what you've experienced:

NHTSA ID Number: 10155437

Manufacturer Communication Number: 05-002-19-3576 (March 27, 2019)

Summary

Some customers may complain of a whining noise from the automatic transaxle when driving at 10 mph and above. The noise: Depends on the vehicle's speed only (the more speed, the more noise)· Occurs with all types of driving (acceleration, deceleration, steady speed)· Does not depend on rpm, gear, or ATF temperature. This is caused by a damaged bearing in the transaxle due to improper configuration of the transaxle case. A modification has now been implemented on automatic transaxles with the following serial numbers: 7TN0820364 and higher (CX-3) / 8TN1090104 and higher (except CX-3) · 8TR1008883 and higher · 8TD1003276 and higher · 8T50331192 and higher (CX-3) / 8T50329705 and higher (except CX-3).

Affects these products:


MAKEMODELYEAR
MAZDACX-32016-2019
MAZDACX-52013-2019
MAZDAMAZDA32012-2018
MAZDAMAZDA62014-2018

The odd thing is the Mazda TSB itself says "2017-2019 CX-5 (SKYACTIV A/T except 2.5T engine) with VINS lower than JM3KF******515940 (produced before November 1, 2018) " Theoretically this should not affect your Signature.
 
That's unfortunate, but I'm glad to see that Mazda stepped up and is making it right, despite of inconvenience of not having use of the car. Here's hoping that's a one-off. The TSB above appears to exclude the Sig and GTR, though I'm sure that could be broadened if the issue is found in those models as well.
 
Thanks for the TSB info. My VIN is quite a bit higher than that and of course the Turbo but still interesting. Didn't realize the naturally aspirated engine and transmission combo was the same in both generations.
 
Good luck with the CX repair and congrats on the MX 30AE!

I too have one of each, except my 2016 MX is a Club.
 
Thanks for the TSB info. My VIN is quite a bit higher than that and of course the Turbo but still interesting. Didn't realize the naturally aspirated engine and transmission combo was the same in both generations.
I was just looking at gear ratio specs in response to another comment and it verifies that the transmission for the 2019 NA engines and the transmission in the 2019 turbos are different.

The ratios in every gear (except 4th) are different, as is the final drive ratio.
 
Just checked my VIN and build date this past weekend. It's subject to this issue, which, is likely present since I'd been hearing a light gear-ish type whine in the 45-55mph range since it was fairly new w/ few miles on it. Shifts normal and smooth still. Now at 13k miles the whine's speed range has widened. Not worrying about it yet until something more definitive occurs such as a drop in MPGs, a noticeable worsening of the noise, or any shifting/performance issues.
 
Make sure they also replace the Transmission oil cooler. From Service Alert: SA-058/19

"When a transmission fails, the transmission oil cooler can become contaminated with debris. If the
old oil cooler is reused, the contamination inside the old oil cooler may then contaminate the
replacement transmission and cause premature transmission failure"
 
Forgot to come back and update. We got the vehicle back last Friday. I don't have the paperwork handy as I am not home but it was pretty extensive what all was done. I will provide another update later on with more info.
 
Make sure they also replace the Transmission oil cooler. From Service Alert: SA-058/19

"When a transmission fails, the transmission oil cooler can become contaminated with debris. If the
old oil cooler is reused, the contamination inside the old oil cooler may then contaminate the
replacement transmission and cause premature transmission failure"
This’s a further proof that a Master Mechanic from my Mazda dealer once told me that the replacement transmission from Mazda will be a remanufactured one, rarely he’d receive a brand-new transmission unless there’s a shortage on it.

SA-058/19 said:
NOTE: If a remanufactured transmission arrives at your dealer without an oil cooler attached, order a replacement oil cooler (with seals & hardware) and install it onto the transmission before installation.
 
So one further update...Back from travel and we spent some time in the car today in the cold and we noticed that...We weren't getting any heat. The air from the vents even up to "Hi" blew room temperature air, unless we were at highway speed, when it would get up to a lukewarm to warm level at max temperature setting. Getting off the highway, the vent temperature quickly dropped back to cool. So...Since we discovered this when we were 10 minutes from our dealer this afternoon so we headed over there and they took it in and we are back in a loaner again. So...Yeah.
 
So one further update...Back from travel and we spent some time in the car today in the cold and we noticed that...We weren't getting any heat. The air from the vents even up to "Hi" blew room temperature air, unless we were at highway speed, when it would get up to a lukewarm to warm level at max temperature setting. Getting off the highway, the vent temperature quickly dropped back to cool. So...Since we discovered this when we were 10 minutes from our dealer this afternoon so we headed over there and they took it in and we are back in a loaner again. So...Yeah.
Your Mazdz dealer could have screwed up the engine coolant re-fill during transmission replacement? Air in the cooling system? Let us know.
 
This is by far the most likely scenario. If they had to disconnect any lines during the tranny replacement and didn't properly bleed the air out of the system then what happens is the air bubble gets "stuck" at the heater core inlet. Sometimes you can temporarily clear it by taking a couple of quick stabs at the throttle. In fact doing this with the radiator cap loose will get rid of the air for you, but unless you get lucky you'll also spew coolant all over the place too.

I actually just went through this little headache this weekend with an older car that I'm getting road worthy again.
 
It was indeed air in the cooling system. Had it back midday Monday. All seems to be in order now.

And so back to the data dump. I reviewed the paperwork from the repair and it stated that they drove the car, heard noise, worked with a master technician to narrow it to the transmission, requested a transmission replacement from HQ and did the work. There's nothing in the paperwork about a transmission cooler, or about the replacement transmission being remanufactured (or to be fair, new - it just says it was replaced).
 
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