I just got my 2017 XLE and now I'm afraid of the transmission issues with the 8AT. I just took a 2k road trip and the transmission isn't the smoothest but it doesn't jerk either. It just hit 93k.
Who do you have for extended warranty?

 

I have an Autonation Extended Warranty with the basic Toyota Warranty. I have the highest type of Autonation Warranty so they cover Engine, Transmission, etc., also did the previous owners ever replace the Transmission on your XLE? By the way, both UA80E (FWD) and UA80F (AWD) have the same issues noted in the ZJC Toyota Bulletin.

 

Here's what Toyota's diagnosis was on the issue:

"Toyota has received reports indicating potential symptoms, such as a whine noise from the transmission while driving, harsh shifting, reduced power, and master warning light/check engine light illumination, in the subject vehicles that are equipped with a model UA80 transmission. There is a possibility that a washer tab, designed to prevent the loosening of a nut inside the affected transmissions, was not sufficiently bent during assembly. This could lead to the nut loosening and, over time, lead to the symptoms described above."

This issue occurred on the 2017 Highlander and the 2017 Sienna, although people have reported the issue with 2018-2022 Highlander Models.

Just search "Toyota ZJC Bulletin" and you will find the documentation, it consists of 5 pages, and addresses the UA80 Transmission had this issue. The only solution is a full Transmission Replacement. That's what's said by Toyota because this issue is from the factory, and is not neglect.

 

@GioXLE at this point just verify it, because the whining started for me in 2024 (7 years after initial vehicle purchase, 65K miles in)

 

The ZJC Support Program is pretty useless, it didn't work on me and many others if you search. Especially since it's 2025 and limited coverage.

 

But it does describe the issue, which is good enough to diagnose the symptoms and know what is causing it.

 

Thanks for all that information!

 

You're Welcome!

 

Also this transmission was not abused, the ATF was changed at 65K miles by the dealer. The harsh shifting and whining noises did not stop. It is a factory issue 1000%.

 

I just got the car back! It feels so smooth and so fun to drive again, no whining sound and warranty took that 10K cost in their face, I only had a $100 deductible to pay. Following the break in procedure. Glad to hear that pure engine sound instead of the transmission whining.

 

did you have an extended warranty on it? How many miles did you have? Trying to get my 17 sienna FWD tranny fixed with talking to corporate. Was your vin on the CSP: ZJC?

 

Hello Friend!




Here's a somewhat summary of this whole situation that happened with me:

(Sorry for writing too much but the story was very long, like It took 13K miles to resolve)

My SE Premium was running all fine between original purchase and 64K miles. I was on a road trip from SF to LA, everything went smooth. about 64,600 on the car at this point. After some time, I drove the car in downtown LA just generally not speeding or anything. The car just started acting weird in downtown LA, at this point the RPM's were spiking and no acceleration response. The car was limping and was going very very slow. I got a traction control alert and I was in Hollywood area so I took it to Hollywood Toyota and they said everything was fine but the ECM had to be updated. So that's what they did. The car was running ok for a return trip to SF, but the RPMs were spiking up and the car was shifting very weirdly. (This is a documented CSP ZJC issue)

I took it to my local dealer when I reached back to San Francisco, they said the Transmission was tested with a shifting tool, and the car was shifting harshly. They told me that looping in my Seller Dealer would be a good decision since they can work better with warranty since my seller dealer was an Autonation Toyota dealer so they are good with Autonation Warranty Coverage. This is when my local dealer gave me a 10K bill for a transmission replacement.

Anyways my Seller Dealer said that my local dealer was saying "BS". Like literally told me that and said they changed the ATF for the car (65K miles in) and they said Transmission was all good. Now the car is still harsh shifting, and soon, the whining sound started becoming evident. So I was getting SO many different statements, from hollywood, seller dealer, and local dealer. It was like my car had different issues found every other dealer.

Fast forward to 77K miles after finding out NHTSA published Toyota Bulletins about the UA80's in these 2017 and 2018 Sienna and Highlanders I took it to my dealer. They told me that my VIN was not included in the CSP ZJC but the transmission had the exact symptoms. By the way the ZJC covered like 66.5K siennas I think but this was a widespread issues (Design Flaw).

So someone had to pay out of pocket and that was of course my Extended Warranty because I had the highest tier. I highly recommend a Extended Warranty they will try to screw once but it won't always work for them. My extended warranty dealer (seller dealer) sent out an inspector and they confirmed the issue with my local dealer. Meaning that the transmission has to be replaced and it has all the symptoms. They first said they would install a used transmission but they couldn't find a UA80E so their only option was to get me a remanufactured transmission (new all inside, casing is old but deep cleaned). New is not an option anymore because the UA80 was introduced in 2016 so they are not made anymore. Components are available so reman is the only option. My exact mileage in was 77,086 miles. I had an extended warranty from Autonation, the Autonation Platinum to be exact. It is the highest type of warranty offered by Autonation. It covers the Engine, Transmission, Suspension, etc. Just anything critical + all small stuff. So everything expensive.

So my stats when the Car had started the Issues:

Initial Mileage when Issue started:

(

64K miles

Warranty:

Autonation Platinum (Highest type of Autonation Warranty)

Mileage when transmission got replaced:

77,086 Miles

VIN covered by CSP ZJC:

No

)

What I also find weird is that my factory transmission that had this issue was made in January 2017, so this is one of the earlier batches ever made. And the ones covered are February till another date I think? So it means my transmission had all the issues from the later dates because it was a design flaw and mine was from that design. And mine failed at 77K? While other UA80's from siennas and highlanders were failing in the first few thousand miles. I think mine was more failure prone than those ones.

Anyways the new transmission that's in my car is from August 2025 so right when I dropped the car in July 2025 and in August when the claim got approved they sent the latest batch to me. I am very happy about that since I know I have the latest updated transmission. I hope you get your car running with a new transmission soon. Thanks for reading this rant!

 

I had an extended warranty that covered Engine, Transmission, Suspension, etc. and the new transmission I got has a 12 month/12,000 miles warranty. Miles with transmission CSP ZJC symptoms: 64K, Miles when transmission failed and replaced: 77,086. My VIN did not apply to the CSP ZJC so extended warranty covered this.

 

The whining sound was checked with a stethoscope and alongside a shifting tool that detects shifting patterns. Was verified of a bad transmission at 64k miles.

 

If you want to check the VIN yourself and verify (some people do this), send a borescope down right around your engine airbox compartment and you will see your transmission, on the right side there will be a sticker and take a picture of that with your phone and match it with the NHTSA bulletins published. This will give you a piece of mind if your tranny is covered or not by CSP ZJC.

 

This is what I am talking about.

 

SN Decoder.

 

Guys I'm getting amazing gas mileage. Just filled up yesterday and topped off and got 414 miles from full tank. That's like the max amount it can get from a full tank. I used to only get 285 miles MTE before. Keep in mind this is because a faulty transmission can significantly worsen the fuel economy of your car. Which was why I used to get 285 miles MTE before transmission replacement.