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RECALL: WRK21 / NHTSA Campaign 21V955000 - Ascent CVT Chain Guide Breakage with CVT Oil Cooler

188K views 984 replies 147 participants last post by  Packard8  
#1 · (Edited)
THIS RECALL HAS SUPERSEDED WUV-07
Unless it's very very specific to something that happened during the WUV-07 Campaign, please keep all conversation in this WRK-21 thread.

ALSO...
If you were a part of this WUV-07 Campaign, you may notice that it has disappeared from your recall list at Subaru's Recall Page, because WRK-21 superseded it.


RECALL: WRK21 / NHTSA Campaign 21V955000 - Ascent CVT Chain Slip/Chain Guide Breakage
  • UPDATE:
    Due to part shortages, the remedy is expected to be available in limited quantities beginning in August 2022.


  • Type: Safety
  • Safety Recall: WRK21
  • NHTSA Campaign: 21V955000
  • Date: December 9, 2021
  • Title: Ascent CVT Chain Slip/Chain Guide Breakage
  • Remedy: Open - remedy not yet available

RECALL DOCUMENT FILES:
4 Affected Products
Vehicles

MAKEMODELYEAR
SUBARUASCENT2019-2020
SUBARULEGACY2020
SUBARUOUTBACK2020
14 Associated Documents

Canadian Owners:

About the new TCM code:
  1. Shift dynamics (I just made up that term, but you get the meaning, I hope) aka shift logic, are changed (improved)
  2. AWD transfer clutch TCM code is updated for smoother operation
  3. Variator pressure regulation code has been changed to ensure variators are fully at clamping pressure (based on torque input) before the forward/reverse changeover mechanism engages the forward clutch
In more detail:
  1. This will address some complaints of how the car shifts (too harsh, at odd times, etc)
  2. This will address the few complaints about shuddering when going around turns, as well as (though not specifically spelled out someplace you all can see) it will address shuddering issues where the rear wheels are taking up a bunch of the drive load when going straight.
  3. This will prevent the chain guide from being damaged, as well as prevent chain slip caused by incorrect variator clamping pressure when the forward clutch is engaged
What it won't do:
  • It will NOT get rid of the chirp. It's a part of how the system is designed.
  • It will NOT fix an already damaged AWD transfer clutch - that will need to be replaced in conjunction with (or after) the reprogramming.

NOTE 01:
The NHTSA Summary was poorly written by NHTSA and confusingly describes the situation. By "improperly secured chain" they mean that the programming doesn't properly set/maintain chain clamping pressure.

NOTE 02:
All
Subaru Ascents that had the previous CVT programming/chain slip recall completed are a part of this recall.

Description
Subaru of America, Inc. (Subaru) is initiating a new safety and emissions Recall for certain 2019 - 2020 model year Ascent vehicles, 2020 model year turbo Legacy vehicles, and 2020 model year turbo Outback vehicles in which the Continuously Variable Transmission (CVT) chain may slip and/or break.

Safety Risk
Due to an improper program, the CVT chain may slip, resulting in breakage of the chain guide. If the chain guide breaks, fragments of the guide could inhibit the shift select mechanism. If the vehicle continues operation with the drive chain slipping, over time the CVT drive chain could break.

Remedy
For all potentially affected vehicles, Subaru dealers will reprogram the TCU. The historical TCU data will be analyzed for chain slip characteristics and the chain guide will be visually inspected. If vehicles are confirmed to be experiencing drive chain slip or if the chain guide is damaged, the transmission assembly will be replaced. For each potentially affected vehicle, all remedy repairs necessary will be completed at no cost to the customer.

Notifications
As required by Federal Regulations, everyone will get physical old-school mail notifications from Subaru of America, within the NHTSA required notification period - and then receive app and head unit notifications.

If you don't feel like waiting to find out, you can check online on Subaru's website.

WAIT:
The remedy is supposed to be available April 2022 May 2022?. Due to part shortages, the remedy is expected to be available in limited quantities beginning in August 2022. As I'd said earlier, my expectation was that Subaru needs the time to release the final programming and get enough of the test tools to all dealerships. That's confirmed in their letter to NHTSA.

Cause Information:
Due to an improper program, if the shift select was moved to drive or reverse (D or R) immediately after the engine was started, the independent secondary pressure control program may allow the forward/reverse clutch (“F/R clutch”) to begin engagement before enough secondary clamping pressure has been applied to the drive chain.
Short version: instead of surge filling the pulleys and then engaging the forward/reverse clutch, it engaged the clutch that sends power through the variators to wheels early.

CHECK YOURS HERE:

CarFax, KBB and the other sites are NOT fully accurate. The only accurate places are Subaru Recall page (link above), Subaru app (once physical notifications are sent), and NHTSA.

More details to follow soon...

Incidentally...
Mine is one of the affected cars.

THERE ARE ONLY THREE CATEGORIES...
@E-EC-ECU perfectly describes the three categories those of us with 2019 and 2020 Ascents fall into

(2021+ Ascent owners have the new programming, and this doesn't apply)

Here's what he wrote, below:

There are three categories of people when it regards to your Ascent and this recall. Just three!
1.) Your car is exhibiting the same behavior advertised in the recall for a slipping CVT chain and/or the guide has been impacted and/or broken off. Or, your transmission is a complete mess and your car is "undriveable".

  • For these folks ... take your car in to the dealership to get inspected and fixed. If it is actively slipping the CVT chain and the transmission is not performing correctly, Subaru will replace the CVT.
    • Yes, you will get a new CVT WITH the new programming as it has already been made available (thanks @Robert.Mauro). If it is a completely separate issue and is still undriveable ... they will fix that too (just like they have been doing for 3 years now).
2.) (My situation) Your car exhibits some "weird" behavior from time to time (rpm instability, shuddering, "searching for gears"), and you think, "heck this might fix all of that".

  • For this set of people ... keep driving your car and take it in when the recall is made available to you.
    • BUT ... If this group ever finds themselves in a situation where their CVT fails and they are now a member of Group 1 (above) ... TAKE IT IN. They aren't going to wait for this recall to fix your car if your CVT is shot. The recall is about inspection subsequent repair if diagnosed. It does not delay any repairs for a known issue.
3.) (These folks I truly feel sorry for) Your car exhibits ZERO indications from this recall, and you are trying to sell it.

  • Not much I can say about this group because the used car market is so high right now, and to NOT be able to sell a car based on a recall that can't be fixed yet is unfortunate .. to say the least. I feel for this group.
The main thing to remember is that this recall is to inspect and diagnose all the potential vehicles impacted by this particular set of circumstances. Hence the tools and equipment being manufactured and delivered to simply make this inspection. If you won't drive your car because of the faulty transmission with a thrown guide arm and other major problems, this recall is completely secondary to your current situation. The recall is simply to inspect the transmissions of applicable cars and proactively replace any CVT that shows indicators.
Basically, if your transmission is a major problem right now, go get it fixed. They aren't going to reference this recall when trying to delay any fix. This recall isn't about the actual transmission repair (CVT replacement), rather it's the inspection and analysis to make sure they catch all transmissions that are exhibiting the behavior. Then, applying the actual repair.
 
#4 ·
I do not believe you can yet. Once the "remedy" (likely the reprogramming file) is ready.
 
#6 ·
I'm ambivalent... other than that I hope @Liberty Subaru has something interesting (cough... Wilderness) to loan me.
 
#9 ·
It tells the CVT what to do. So, short version is, the ECU tells the TCU "hey, here comes 231.7 lb-ft of torque". The TCU does some math and says "ok, the chain clamping pressure needs to be ###psi" and sets the pressure.

In this case, the ECU calls for a shift, the TCU does some math, sets pulley ratio and relevant clamping pressure. Instead of setting the pressure steady, it's setting it wrong, and/or jumpy, and/or low, allowing the chain to skip or slip.

When the chain does that, it can break the chain guide. I'd surmise that the chain constantly being jerked extra taut and then loosened, and/or a chunk of a broken chain guide running under the chain onto the pulley, when the chain is riding closer to the center of the pulley, can cause the chain to break.

In either event (chain slip, or chain guide broken), the CVT will get replaced.
 
#11 ·
Mine gets the nod for this recall. I haven't noticed any issues, but the nice folks at my Subaru dealership will get to run the diagnostics, etc., when the time comes.
 
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#12 ·
Sadly my Subie is a part of this too :(...any thoughts on what the symptoms I should be watching for, so I can inform the dealership when I take it in.
Also, any ideas when the repairs will start? I got an oil change coming up this week, wondering if they might take care of it then already...

Thanks so much for posting this...appreciate the heads up.
 
#13 ·
Sadly my Subie is a part of this too :(...any thoughts on what the symptoms I should be watching for, so I can inform the dealership when I take it in.
Also, any ideas when the repairs will start? I got an oil change coming up this week, wondering if they might take care of it then already...
I wouldn't expect them to be taking care of it this week. If you've ever felt a clutch skipping, I think one of the symptoms feels like that.
 
#15 ·
Thanks for the info and link Robert. My VIN is included in this recall as I expected it would be.

Haven't had even a hint of any trouble so far, the CVT is always butter smooth.

I appreciate Subaru's attention to these potential problems.
 
#19 ·
I'd think that they'd feel different potentially, but that unless a 2019-2020 exhibited the fault symptoms, one wouldn't feel that difference.
 
#20 ·
For what it's worth, the 2021 Outback XT loaner that I had a month or so ago drove pretty well compared to our Ascent. I wrote about it a little bit at the time. Our Ascent drove better after the TCM relearn they did, but it's mostly gone back to what it was doing prior to the relearn. I wonder if some of the stuff I feel in ours is due to small chain slip events that weren't really a factor during the transmission's relearn due to very conservative baseline values...the small slips not significant enough to cause a massive squeal event, but just enough for a momentary impulse...I wonder if all of that will be cleaned up with the revised program and the Outback XT is really what my Ascent should drive like...

I can't lie -- I'm pretty excited for this recall.
 
#40 ·
I just today got my 2021 Outback XT back from having its transmission replaced, with only 5,800 miles on it. It's build date was some time in September 2020. I brought it in because it was making sounds coming from the rear end and shaking a bit when making a left or right turn from a stop. Never really experienced any issues in a straight line. According to the service manager, they got the transmission to bind up any time they accelerated and cut the wheel hard. According to the paperwork, the tech heard noises more in the front diff area. They drained the fluid, found it dark and smelling burnt, and ordered a new transmission.
What worries me, is that the very first turn I took in the car from a stop after getting it back, it made the exact same noise that I brought it in for, which to me still sounds like it's coming from the rear end. Brought the car straight back and went for a ride with the service manager to make sure he heard what I was experiencing, which he did. . Seemed to think it's normal because the extra torque from the turbo. I want to believe that, but I just don't know anymore. I just have this uneasy thinking that I'm going to be replacing the transmission again. When Subaru of America calls me back later this week to ask how the repair went, I'm going to mention that to me it feels like I'm going to end up having the same problem again.
 
#24 ·
That depends on production date and other factors, for instance, this will be my third, but, unlike Bphillips32_nj below, the AC line wasn't one of mine.
This new recall makes four on my 2019.. dropped car off yesterday for the AC recall and they told me about this new one!
My third - fourth if you're counting the ECU reprogram. Mine were PCV valve, CVT chain slip (harness) recall, and ECU customer satisfaction.
Our 2020 is not part of this. Might this be a case of “yet”? Are the boffins at Subaru sure enough about which cars are affected that they won’t be adding more?
What is the production date of your 2020? 2020's produced after a certain date aren't in the recall group - probably because they're running different TCM code.
 
#38 ·
Nope. I'm guessing the pump in question didn't make it into the Ascent production line until later on (my Ascent was built on May 30th, 2018 in the first batch). So, I lucked out on that one.
 
#43 ·
My "fresh out of the womb" (Oct 2021 build) seems to have trouble deciding which ratio is appropriate when accelerating from 25-30 MPH with a normal throttle input....it wants to bog, almost like a premature TC lockup, then it selects a lower ratio and lets the turbo spool a bit. I think it needs to go back to school. I'd be happy to lose the simulated, stepped faux shifts in favor of letting the CVT do what it does best, deliver smooth transitions in ratios as required by throttle position input, engine load, etc. Seems like it wants to get to "high gear" really early, in order to satisfy the EPA/MPG goals. Hopefully, a better TCM program with better shift logic is in the offing.
 
#35 · (Edited)
5th recall for me. CVT was replaced at ~4700 miles, about 6 months before the initial harness recall and TCU update. Interesting that they are still pushing new updates. No noted issues in 32k miles since the original replacement.

Just for information my progression in reverse time order below. Still love my car, just sharing my experience. I suppose once it flips from "remedy not available" Subaru will let me know it's time to come in.

Type: Safety|Safety Recall: WRK21|NHTSA Campaign: 21V955000
Ascent CVT Chain Guide Breakage with CVT Oil Cooler
Open-Remedy not yet available
Incomplete

Type: Customer Satisfaction|Service Campaign: WRK20|NHTSA Campaign: N/A
2019 ASCENT A/C EVAPORATIVE COOLING PIPE REPLACEMENT
Completed Jan 2021

Type: Safety|Safety Recall: WRD20|NHTSA Campaign: 20V218000
19 Ascent Fuel Pump Replacement
Completed Apr 2020

Type: Safety|Safety Recall: WUV07|NHTSA Campaign: 19V855000
Ascent CVT Chain Slip
Completed Nov 2019

Type: Customer Satisfaction|Service Campaign: WUU06|NHTSA Campaign: N/A
ECU Reprogramming C1424
Completed Nov 2019


~May 2019 - Transmission failed and was replaced under warranty at ~3 months and 4700 miles.
 
#37 ·
I jumped into Subaru with great enthusiasm a couple of years ago when I was looking for a mid size SUV. I grew up on the West coast and the brand was very popular there. However...I will admit that I am pretty discouraged with Subaru at this point. I've had to replace a battery and am requiring a 3rd brake change because of, "Whistling" and my 3rd set of seat ventilation fans because of rattling. I am getting things fixed, but the fix doesn't fix the fix. And now this transmission recall. My Ascent only has 18k on it and it has spent more time in the shop than my Dodge Ram did in 50,000 miles or the Volkswagen before that. In fact , more than both of them combined now that I am thinking about it. I am seriously considering parting ways with this car.
 
#383 ·
I spent the better part of a 43 year career conducting failure analyses on mechanical and electronic components and systems and I was involved in determining the fixes that needed to be made to address the root causes and whether or not the failures were recurrent to a statistically significant degree or had a latency aspect to them where functioning units in service would eventually fail prematurely. I worked on the planning and implementation of many field recalls and fixes.

I find Subaru's lethargy in making the fix for this latest Ascent recall available maddening. This recall was publicized late last year. nearly 5 months later, there is still no fix available. This problem affects driveability, potentially affects safety, and even if your vehicle hasn't manifested any symptoms yet, it may result in significant damage at some point in the future requiring non-trivial repairs. The the mechanical components involved may already be incurring non-catastrophic damage to varying degrees as the affected vehicles accumulate more mileage. Also, anyone who drives their vehicle below average miles per year should be very concerned that when their warranty time period expires before the maximum covered warranty mileage is attained, that the time for the failure mode described in the recall to occur will be outside the warranty period.

This is exactly what happened to us when the 2009 Audi A4 we purchased new was found to have a design defect that resulted in excess oil consumption that worsened over time and mileage accumulated. That problem was the subject of a successful class action lawsuit that forced VW-Audi to do a recall and essentially a full ring job on vehicles that were above a certain threshold of oil consumption by a certain date. Well, my wife drove our A4 about 5K miles per year and during the time frame the full fix was allowed, our oil consumption was measuredd by the Audi dealer as being just below the threshold to be eligible for the full fix (which was about $4200 for ring job on the 2.0T engine). They did a less extensive band aid fix, but without the ring job, which replaced the old rings with ones manufactured to tolerances that would fix the root cause of the problem, any vehicle affected would eventually experience worsening oil consumption to the point where a ring job would be required (outside of warranty) anywhere from about 50K to 80K miles. Try selling a car with that known issue.

Suburu needs to get off the dime and make a fix for this WRK21 recall available ASAP. At the very least, they need to issue an update to affected owners advising us of the status of the fix and providing some definitive insight (not just vague marketing pap) as to why it is not yet available and a target date for it being available if it isn't available in April as previously stated in the recall notification.

Suburu can sure as heck send me lots of marketing emails with cute dog accessories, how about an update on the fix for this serious issue? Suburu expects me to just fly their Boeing 737 Max Ascent until the SW programmers figure out a programming fix (which I am puzzled by, if in fact this problem has been fixed on 2021 model year Ascents) or until Suburu has, at their leisure, provided the dealers with the tools and diagnostics to inspect for timing chain and chain guide damage. I'm pretty peeved at the extended time this fix is taking to incubate at Suburu with no recourse available to owners of affected vehicles.

This combined with the multiple battery failures and ineffective fixes for parasitic voltage leakage have made the purchase of our 2020 Ascent Limited a mistake and the last Suburu purchase we will ever make.

This thread contains comments that are in the category of turd polishing that doesn't extinguish the stench of Suburu's laissez faire approach to fixing this problem.
 
#39 ·
I have to agree with Cosmo. I still love the Ascent and appreciate Subarus willingness to make these fixes, but these recalls are certainly annoying and now starting to get to me. Plus, I was just in the shop twice as the dealer cant replicate my banging strut noise. They better get this programming right as I think another 1 or 2 transmission recalls may mean this is my last Subaru, though I will have this one for awhile.
 
#45 ·
Recalls are a good thing...consider that "back in the day" manufacturers tended to sweep things under the rug a whole lot. A recall means something is being taken care of. It's customer service. Since Subaru has determined there is something potentially causing issues with a range of vehicles, including my own, I'll be very happy to bring mine in to get it addressed.

It might seem like there are "a lot of recalls", but this is not unusual for the entire industry at this point and while this one is Subaru specific, there are a lot of shared parts in the industry with "yuge" recall efforts across multiple brand names for essentially the same thing in some cases.