Refer to TSB 07-213-22R which upgrades the battery.
The original battery was SOA821B700. The upgrade battery, if is is installed, is SOA821B900.
The TSB does not provide battery info.
Look up the part numbers on subaruonlineparts.com and hopefully it has the specs. You can always ask. Their rep is on this Forum.
The label on your installed battery will say what it is.

TSB 07-178-21 is for battery testing and charging.
You can probably find the TSB on the Internet.
I have a 2024 and it is different.

Check related Threads below.

 

Refer to TSB 07-213-22R which upgrades the battery.

The bulletin says Outback, Legacy, and Ascent.

 

I have a 2023 Limited. I park outdoors and the weather is nasty here today, but when things clear up I can go pop the hood and take a look. No guarantee it will be the same from 2022 to '23, but my guess is very similar if not identical since the model refresh didn't kick in until '24.

 

The weather cleared up this morning and I was able to take a look at mine ('23 Limited, 2.5L engine). There is no obvious branding on the battery, but there is a sticker that says "Sold by Subaru of America."

The battery is a Q-85 and says it is "for stop & start" so I assume it is more capable than what is installed in non stop/start model cars. It also says 20 hour, 62 Ah and 620 CCA for electrical characteristics, which is somewhat beefier than some of the ones described previously in this thread.

Hope that helps.

 

The battery in my 2023 says 470.

Canadian model. Dunno if we get stronger batteries up here or not.

 

That would be a metric battery. You have to double CCA and add 30.

 

Check the owner's manual. For 2023, Crosstrek models without Auto Start Stop system use a 75D23L and models with Auto Start Stop system use a Q-85. Specs for both are available on the internet. Costco's basic Group 35 battery meets the requirements for both batteries and has a great warranty. Keep it fully charged with a 1A smart charger to compensate for parasitic current discharge and it should last for five or more years.

 

models with Auto Start Stop system use a Q-85. Specs for both are available on the internet.

To be clear this is not true. Q-85 and Group 35 (and 75D23L) tell you physical characteristics, not electrical characteristics. This is the underlying issue. Just because a battery fits in the engine bay does not mean its specs are the same as another battery that also fits. The remark about a battery meeting the requirements is the crux of the issue. Nobody can claim this when nobody knows what the requirements are. Unless someone knows what was originally included with the vehicle and, ostensibly, works or is prepared to do whatever testing the manufacturer did to decide that battery was good enough.

Canadian model. Dunno if we get stronger batteries up here or not.

That would be an interesting question to get the answer to.

 

Tried to find the Subaru 'Build Sheet'. Mission failed.
But, I did find this link: Welcome to VIN Decoding :: provided by vPIC
Unfortunately it is pretty useless. No 'build' details are provided.
The only way I can figure out what the OEM battery is for my Subaru is look at the label on the top of the battery. It is the battery installed at the factory so it is what it is.

Go to your local Subaru dealer Parts Department. Ask them for the price and availability of the battery for your Subaru based on its VIN. If they have it in stock ask to look at it. You are not under any obligation to actually buy it.

 

Open the G.D. hood and look at what battery is in your ride? CCA info, size, etc should all be there!!

Did you ever take the time to speak with a Subaru parts department? You know they can inform you of what size is required and up to what size will fit depending on your vehicle's trim level.

You can also peruse many on-line auto parts stores like O-Reilly's, AutoZone, Advanced Auto, Napa, etc. They too will give you options on-line or in person specific to you vehicle's requirements.

Majority of the OEM batteries used in the the CT for the last 5 years have changed manufacturers due to the vid and supply chain issues of the past. There are only three major vehicle battery manufacturers left and they ALL make batteries for many different customers. Batteries in the last five years have also gone thru cutting corners, hence they are no longer warrantied as they used to. If you find a battery with at least 3 or 4 year warranty, that would be your BEST bet at this time. Gone are the days of the Sears Die Hard Platinum 7 year. They just don't make them like they used to.

Add the fact that manufacturers are now tightening the charging parameters of the 'not so' smart charging alternator and higher electrical demand for all the tech...you now have a recipe for batteries going out sooner.

Personally, I always upgrade to the largest CCA battery that will fit in the OEM spot. I prefer more CCA than stock, and have never had issues upgrading to such. If the dealer carries an OEM with more CCA, I will usually compare to others on the market before committing to a battery.

So no, you will not see consistent information, because things regarding the battery/charging system is ever changing and different than just a few years ago. Again, highly recommend you speak to a Subaru parts counter and ask your questions if you are looking for something specific or plan to upgrade the battery. ALL on-line forums/chats/sites are not 100% reliable. Go to to the source if you want straight answers.

 

Open the G.D. hood and look at what battery is in your ride? CCA info, size, etc should all be there!!

Did you ever take the time to speak with a Subaru parts department? You know they can inform you of what size is required and up to what size will fit depending on your vehicle's trim level.

You can also peruse many on-line auto parts stores like O-Reilly's, AutoZone, Advanced Auto, Napa, etc. They too will give you options on-line or in person specific to you vehicle's requirements.

Majority of the OEM batteries used in the the CT for the last 5 years have changed manufacturers due to the vid and supply chain issues of the past. There are only three major vehicle battery manufacturers left and they ALL make batteries for many different customers. Batteries in the last five years have also gone thru cutting corners, hence they are no longer warrantied as they used to. If you find a battery with at least 3 or 4 year warranty, that would be your BEST bet at this time. Gone are the days of the Sears Die Hard Platinum 7 year. They just don't make them like they used to.

Add the fact that manufacturers are now tightening the charging parameters of the 'not so' smart charging alternator and higher electrical demand for all the tech...you now have a recipe for batteries going out sooner.

Personally, I always upgrade to the largest CCA battery that will fit in the OEM spot. I prefer more CCA than stock, and have never had issues upgrading to such. If the dealer carries an OEM with more CCA, I will usually compare to others on the market before committing to a battery.

So no, you will not see consistent information, because things regarding the battery/charging system is ever changing and different than just a few years ago. Again, highly recommend you speak to a Subaru parts counter and ask your questions if you are looking for something specific or plan to upgrade the battery. ALL on-line forums/chats/sites are not 100% reliable. Go to to the source if you want straight answers.

When my OEM battery kicked the bucket at just under 4 years old, I replaced it with a Duracell Gold AGM 5-year warranty battery. We'll see how long it actually lasts lol.

 

As PNW Crosstrek pointed out, service manual descriptions list two batteries; for 2.0L cvt - 75D23L/470A/53 Ah , manual - 55DL23L/390A/40 Ah.

Specifications are subject to change without notice.

Every vehicle manufacturer buys batteries in bulk from suppliers meeting specifications. New car batteries have separate warranty programs similar to tires. Subaru, like many manufacturers, either relabel batteries from battery manufacturers or use brands with original labeling establishing close association to a product (GM/AC Delco). Battery failures under warranty were replaced but no one from Subaru reported battery issues from battery fault, faulty telematics discharging batteries or smart charging systems failing to maintain full battery status.

 

...but no one from Subaru reported battery issues from battery fault, faulty telematics discharging batteries or smart charging systems failing to maintain full battery status.

^^
This, unfortunately, is the norm with most manufacturers today None of them will take ownership of either faulty batteries, faulty draining telematics, or smart charging issues without a barrage of complaints to NTSB. When "safety" is of concern, then something will be done. Otherwise it may take several years for a manufacturer to put out a TSB (perfect example Subaru and the Outback telematics draining). No one wants to admit to a problem, and will blame it on someone else. Dealerships would rather just replace batteries than deal with actual electrical/charging issues. At least that seems to be the norm right now according to the few forums/sites I frequent.

Every auto manufacturer is going thru the same growing pains with batteries, charging systems, and telematics as Subaru. Some are just easier to diagnose/remedy than others, but all of them are doing the same song and dance when it comes to this specific topic.

Hopefully as more complaints come in, something will actually be done on the redesigning end of things. We can only hope.

 

Every vehicle manufacturer issuing technical service bulletins always includes a warning;

TSBs are quiet admittance to issues, short of a national recall likely involving NHTSA. The DCM, battery, and thermo control valve TSBs are voluntary, addressing failures requiring replacement, upgrades, redesign, whatever, to correct unforeseen problems when enough were reported (from dealers) to have Subaru investigate and correct them.

A recent discovery by two curious individuals about Starlink security revealed an unknown weakness allowing telematics data and remote access to virtually every Subaru using Starlink. Realizing this, they contacted Subaru with their findings. Subaru accepted and immediately revised software to ensure Starlink security.

Vehicle manufacturers usually take responsibility for failures sooner or later, depending on whether for safety or mechanical/electrical/electronic/software changes. Some may take into account repeated failures from reports from dealers or from individuals finding flaws in security and sharing it with manufacturers to help.

 

Skip the line. Get an AGM battery.

 

While AGM have there place, the charging systems on some new vehicles (smart charging) will not charge an AGM any better. In fact, you may get worse battery performance. I do not know if the new CT has a way to indicate/input which type battery has been installed?

I know for at least newer Nissans, there is no way add the AGM, unless you disconnect/de-pin the smart alternator sensor.
Fords technicians, can go in to their system (Forscan), and change the type of battery in the ECM/DCM to have the smart alternator adapt properly.
Again, not sure what the new CT allows or if it recognizes the AGM all together??

 

From '24 service manual;

No mention of replacing batteries and registering or other methods to recognize whatever battery type replaces the oem battery. Remove and replace.

 

I am ASSUMING the SM also 'recommends' an OEM battery as a replacement...which means a regular wet battery?? Again, not an expert, but know of many many many people who have the same thought process of 'upgrading' to an AGM, only to find out the not-so-smart charging parameters of the vehicle, do not match or can be changed to an AGM type battery. This is one reason why folks disconnect/bypass the smart charging system. AGM require a different way of charging than a wet cell.

Again, I do not know if replacing with an AGM in our 24 and newer CTs would be 'automatically' recognized, need that info put in somewhere, or just shouldn't be done??

I am not saying you cannot or shouldn't put an AGM. I am simply stating to verify that the charging system is set up to charge your more expensive AGM battery correctly. Otherwise, IMO, you are just spending more to end up with the same results with a regular battery.

This is yet ANOTHER strike against the not-so-smart charging system IMO. Years ago, you could put whatever would fit in your ride, and be off with no problem. Now more B.S. hurdles to jump just to change out a simple battery what joke!!

 

The AGM battery I put in my 2024 CTW seems fine. I read consistent power output if I have my Spod on.

 

Automatically recognized as I figure it would have told me in the last year...

 

Not necessarily. Most folks assume the AGM is fine, until about a year, when it goes bad.
Your best bet is to verify with the Subaru parts desk and see if THEY offer an AGM for the CT. And if so, ask them if anything needs 'updating' in the vehicle prior to installation? You know they would be more than happy to sell an AGM, so if it is possible, they will tell you
Again, just my two cents before opting to change to an AGM.

EDIT: I'm all for anyone going AGM ... just make sure the damn charging system is set up to handle charging it properly is all.

 

Well, I had the dealership put it in just in case there would be issues. Zero.

 

Sounds good. So this tells me installing an AGM IS possible.
However, it doesn't answer the question for those DIY "IF" any configuring is needed to accept the AGM, or if its just a drop and play?? This then would be the $64,000 question???

Thanks for letting us know @General Martok

 

So, I just called my local Subaru dealer's parts department and asked about installing an AGM in our 24 CTW. He stated that model will not support an AGM, only wet batteries!!

So now I'm curious as to if the Wilderness line has something different, which most likely does not, the parts counter guy was incorrect, or what???

So I'm asking others here to contact their local dealers/parts departments and ask them if THEY know if an AGM battery CAN/SHOULD be installed in the 24 and newer CT?? I would be curious as to the results Something is not right here

 

I can't find the reference right now, but I remember reading Subarus with 'SMART' charging begin a new map whenever the battery is disconnected. From what I remember also, this doesn't matter if it's a EFB or AGM.

I also remember at one of the battery sites which referenced CHARGING a fully sealed battery. These include AGM, EFB etc. Batteries considered LOW or NO maintenance ARE vented to the air if only thru a SMALL vent.

This leads to 2 anomalies ... EFB and AGM (sealed) batteries should not build up any residue on the battery terminals since there should be NO gaseous venting. Second, FAST CHARGING of AGM or EFB (sealed) batteries can be dangerous as there may not be enough internal space for acidic action and cause internal pressure and heat.

Feel free anyone to add to this discussion as I see it's OFF THE RAILS from the original posters request.

 

I can't find the reference right now, but I remember reading Subarus with 'SMART' charging begin a new map whenever the battery is disconnected. From what I remember also, this doesn't matter if it's a EFB or AGM.

I also remember at one of the battery sites which referenced CHARGING a fully sealed battery. These include AGM, EFB etc. Batteries considered LOW or NO maintenance ARE vented to the air if only thru a SMALL vent.

This leads to 2 anomalies ... EFB and AGM (sealed) batteries should not build up any residue on the battery terminals since there should be NO gaseous venting. Second, FAST CHARGING of AGM or EFB (sealed) batteries can be dangerous as there may not be enough internal space for acidic action and cause internal pressure and heat.

Feel free anyone to add to this discussion as I see it's OFF THE RAILS from the original posters request.

Here's a partial reprint from '24 service manual.

 

BTW, here's a post where an AGM battery was installed in a Wilderness. It IS an LN2 or Group 47 battery as is called for.

https://www.subaruxvforum.com/threads/my-wilderness-mods.187997/?post_id=2186770#post-2186770

 

I appreciate the AGM info , but this does not answer whether the vehicle can support an AGM on it's own. Sure the battery will fit and run for a while (usually a year), because it is not supported like the wet batteries.

As far as the new map, I do believe it is just a restart for the reminders to check the battery?? But I'm not 100% sure either.

 

This is a topic that's been brutally beaten to death here in the past. As someone who was forced to read all of the back and forth, I can confirm that an AGM battery will work in all of our Crosstreks, but the car's charging system will not optimize for it ... which means to me that it's not going to be worth the premium cost. That said, the inefficiency isn't such that an AGM in a Crosstrek is going to conk out in a year.

 

So in other words, it will work, but about as well as a battery you'd pay less for?

 

This was my point as well.

Again, I'm all for 'upgrading' the battery to something that lasts longer...IF IT DID LAST LONGER. Who wouldn't?
My point was to just educate and/or inform those who ASSUME an AGM will just last longer because it's a better battery.

So it appears, at least for now, the 24 and newer CTs charging systems are not configured for AGM batteries (like most modern vehicles with the not-so-smart charging systems)?

Do your homework and due diligence. Verify the charging system is compatible. All batteries ARE NOT the same.

 

Yep, pretty much.

 

i think since crostrek alternator can output up to 14.5v it will work with AGM, however not sure if it will maintain the battery at full charge all the time. this only can be tested regularly and for those who have used agm maybe can share jow long their AGM lasts.

typical efb battery on car without accessories running while parking and driven daily should last very long.

for mine, the killer part is heat and parking camera that will run until battery reach 12.5v, so basically the battery may end up with 70 percent capacity after few days parking.
so far never a problem to start the car after 15 days parking. I havent got courage to pay 2.5-3x of agm price since my efb battery still last 2 years plus every time.

 

i think since crostrek alternator can output up to 14.5v it will work with AGM, however not sure if it will maintain the battery at full charge all the time. this only can be tested regularly and for those who have used agm maybe can share jow long their AGM lasts.

AGM require different charging parameters set for optimal use, compared to wet. This is why 'some' higher end vehicles (Porsche and BMW to name two), allows the tech/owner to input the TYPE of battery being installed so the charging system can act accordingly. Plus "vent kits" are available as accessories for those wishing to switch to AGM, as most of the batteries in these two brands, go under a seat!!

I can only go by the countless forum posts (on other forum sites) regarding AGMs not lasting long in vehicles with the smart charging systems. Many of the owners who added accessories or mods to their vehicles, needed more constant and consistent battery voltage to not only provide proper power output, but to avoid the ever so sensitive sensors of other so called "safety" features from being triggered and throwing out error codes or CEL. This is where the disabling or by-passing of the smart charging system took root.
Some vehicles then saw much greater improvement on the constant and consistent charging of the batteries. But yet the AGM crowd had mixed results. Turned out the smart charging systems were created for the basic batteries most vehicles get...wet!

Fast forward a few years later, and most vehicles STILL are not optimized for the newest and most up to date batteries?? Since then, most posts regarding the AGM battery are negative. Initially people have great results out of the gate, but longevity is where it takes a hit. I have heard of folks going back to wet batteries after only a few months, and some lasting over a year before deciding the cost is not worth getting another AGM. So basically a year is what I have read is the average IMO. Just giggle AGM results and you will see for yourself.

Again, some companies are now allowing their vehicles to have the AGM as an option. Obviously Subaru has not caught up with this trend yet, at least on the CT line??

 

EFB/Normal Pb don't charge up to as high of a voltage as AGM.
This is why you can put AGM in an EFB/Pb vehicle, but not vice-versa.

However, because of this, you won't make the most out of the AGM, and I'm not sure if AGM has issues similar to EFB/Pb when under voltage (ie. sulfation).

IMO just get a decent brand EFB and be done with it.
They are more energy dense then similar sized Pb/AGM so are probably better if you're running dashcams etc.

 

Link to a good article at battery University about AGM battery pluses and minuses. They are less prone to sulfation than flooded type, another benefit for those who don't take longer drives is they take uptake charge faster than flooded. I've had AGM batteries in four vehicles in the past two of which lasted a little over seven years, one that made it to 8 years and one that only lasted about 5 and 1/2 years.

BU-201a: Absorbent Glass Mat (AGM)

Learn what differentiates Absorbent Glass Mat (AGM) batteries from other lead acid battery types

batteryuniversity.com

.

 

Working fine.

 

That is because the smart charging sensors installed on those older vehicles you put those AGMs in, were older versions. The charging parameters and sensors in today's vehicles are even more strict. Version 1.0 from years ago is not the same as Version 2.0 or whatever version they are running now. The trend of 'fuel saving' has choked everything in these vehicles to the point if you sneeze you may set off a CEL

Auto Start/Stop (A.S.S.), active shutters, smart charging, etc ALL are meant to save fuel and give companies CAFE carbon credits...that's it!! All these systems have been proven to cause more harm than good. The consumer is left to deal with the consequences in repairs associated with these systems, including replacing the battery more often or having to deal with trickle charging more as opposed to several years back when this was not even practiced by the daily driver.

I had several vehicles in the past that I never had to replace the OEM battery. Lasted 8 years or more without issue. Today is a different story.

Just because it worked several years ago, doesn't mean it will work today. Unfortunately, like other here, we have to learn to adapt. I just choose not to adapt quietly if I can

That is because the smart charging sensors installed on those older vehicles you put those AGMs in, were older versions. The charging parameters and sensors in today's vehicles are even more strict. Version 1.0 from years ago is not the same as Version 2.0 or whatever version they are running now. The trend of 'fuel saving' has choked everything in these vehicles to the point if you sneeze you may set off a CEL

Auto Start/Stop (A.S.S.), active shutters, smart charging, etc ALL are meant to save fuel and give companies CAFE carbon credits...that's it!! All these systems have been proven to cause more harm than good. The consumer is left to deal with the consequences in repairs associated with these systems, including replacing the battery more often or having to deal with trickle charging more as opposed to several years back when this was not even practiced by the daily driver.

I had several vehicles in the past that I never had to replace the OEM battery. Lasted 8 years or more without issue. Today is a different story.

Just because it worked several years ago, doesn't mean it will work today. Unfortunately, like other here, we have to learn to adapt. I just choose not to adapt quietly if I can

Believe me those vehicles I put the other 4 agms in did not even have Smart charging systems. I wouldn't have one if you paid me. I would never even have bought my 2019 Crosstrek if it had smart charging. I also would not buy any vehicle that had auto start/stop...that is such bullshit just to try and scrape a few more tents of a mile on the mpg numbers lol.

 

I hear you and completely understand. Unfortunately, this is the direction they are all going. Many of us like minded folks out there are in the same boat. We have to learn to embrace the suck as they say. I just choose not to go quietly like others

$h!t is moving tooo fast for us olderrrr drivers to keep up with. Tech, added safety features, and 'save the planet' mouse traps are all reeking havoc in todays vehicles IMO. Grew up learning to actual drive the vehicle, not rely on more doo dads to tell me how to drive Just still used to simpler times I guess? Not ready for someone/something else to take over driving for me yet!!

 

Still drive my 1996 Oldsmobile LSS as my daily driver. Really comfortable old folks car that I can actually see out of. Just recently a tire got so dry rotted it went flat in the car port. Towed the Olds to the tire store and put on new tires. Then the water pump leaked like crazy so had that replaced. Only 200k miles on the water pump. 4 speed automatic and 3800 Series II engine. Everything is worn out and leaks, but it gets me to the grocery store. The only reason why I bought a Wilderness was to drive off road on my Tree Farm. Gets me there and back in style. Turn most of the techy stuff off if I can, but once the RAB kept me from running over a pedestrian when I was backing out of a parking place. Tech saved my 'butt', I am good with that. Thanks to the members of this Forum and YouTube videos I am gradually learning to 'cope'. My Subaru dealer is only a couple miles away and they are really great.