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Battery replaced with SOA821B900

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50K views 95 replies 30 participants last post by  ATXV18&Ascent19  
#1 ·
I took my 2021 Ascent the the dealer for the ground bolt recall today. I also mentioned that I've had to jump start my car a few times after it sits unused for a few days. My battery tested to 508 COA (defect sulfation/ degraded). I was hoping for the B600 battery mentioned in another battery thread. But apparently their is a newer TSB that now specifies the SOA821B900 with 750 CCA. That's what they put in mine under the 3 year 36 month warranty. It was a nice surprise.
 
#3 · (Edited)
Nice upgrade. Is it a Standard Flooded, Enhanced Flooded, or AGM type? I recently had my OEM B400 replaced with the B600 (EFB). I'm glad they are recognizing the problems with the weak OEM and correcting them.

Looking up the part number, it's odd that the B900 retails for $235, vs $395 for the B600 EFB type.
 
#5 ·
I wonder if it is standard flooded, enhanced flooded, or AGM???

At any rate, a 620 CCA battery is better than the OEM 530 CCA loser.

I wonder why SoA is so "penny wise and pound foolish" with their selection of OEM tires and batteries.

Are you listening SoA?
 
#8 · (Edited)
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It's an EFB with 750 CCA. I also wondered why it's cheaper than the B600. But I'm not complaining
Well shoot..... I wish my B400 would have lasted a few weeks longer before dying. I did get a B600 EFB as a replacement, but the B900 looks better still. The photo looks like it is larger, did they replace the battery tray, and cut the insulation jacket to reveal the electrolyte level? If I keep the car long enough, I'll probably go with a high capacity AGM the next time.

I'm glad to see that SoA finally woke up and is no longer replacing one junk battery with another junk battery. Now, let's see them address the junk Falken OEM tire situation....... (y)
 
#10 ·
PS: Looking at your photo, it appears that they forgot to apply an anti-corrosion coating to at least the - terminal, (can't see the +). I'd bring that up at the next visit, or just buy a spray can at any parts store. (y)
 
#12 ·
Looking at your photo, I don't see any fill caps, like the B600 has. The B600 also has visible "full" and "add" lines on the front of the battery, and the case is transparent. Perhaps the B900 is sealed, like an AGM?
 
#24 ·
When the battery in our 20 Outback was nearing the end of its life after 18 months, I called SOA and told them AutoZone tested and verified a bad cell and the replacement cost was about $200. On the spot I was told get it done, send the receipt, and within a few days I received a check in the mail. Three years later I'm still on that AutoZone battery. It's an EFB, not an AGM, same as the OEM battery but higher CCA.
 
#39 ·
Yeah. That’s what we are thinking too. The Ascent has been relegated to local driving now. I’ll still put a high capacity battery in it. Seems like the way to go for peace of mind. We bought a 23 Honda Pilot for the big trip vehicle. Her daily driver. The Ascent is now my daily driver. Not a bad deal for me. More space and more horsepower coming from a Crosstrek, I’ll take a hit on gas but me driving it for a couple of weeks, I get better gas mileage due to a little highway driving than my wife’s in town driving.
 
#42 ·
I'd be interested in your thoughts comparing the Pilot to the Ascent. We had it narrowed down to those exact two vehicles and chose the Ascent for
1) One inch wider third row and one inch more depth behind the third row for cargo.
2) Familiarity with the same big screen we've enjoyed with our 20 Outback, which we kept.
3) $9K less expensive comparably equipped, $15K less expensive when you consider that only Touring and Elite offer live HondaLink that is comparable to Starlink on the Premium Ascent.

The lowest Pilot we would have considered was the EXL with the 9" screen, we ended up with a Premium Ascent.

Getting back to the topic of this thread, we do not have this newest, biggest battery in our Ascent but will certainly keep it in mind if we ever need it.
 
#41 ·
The photos posted don't seem to have a BCI rating, only "LN", maybe that is a new spec? When my B400 was replaced with a B600, it required a larger tray, and the insulating jacket was cut out at the front to reveal the "add and fill lines" on the transparent case (EFB with filler caps). The B900 doesn't have filler caps, looking at the photos.
 
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#63 ·
I believe the TSB calls for the B900. I had mine replaced several months ago, before the current TSB. I got a B600, EFB with the transparent case. I'm guessing that absent the TSB, my dealer installed whatever "better" battery they had at hand. What is odd is that the B600 is much more expensive than the B900 if bought as a stand-alone part, though the B900 has a higher CCA rating.
 
#66 ·
So does the 2023+ models come with the SOA821B900 battery from the factory?

Looking on Autozone's website, 2023+ model battery size is listed as size 47. Other sites list the battery as H5 or LN2. Can anyone with more info verify the size of the SOA821B900? I'm am interested in upgrading for my 2019 model.
 
#67 ·
For either the B600 or B900, you will need to upgrade the tray and hold-down (AFAIK). I believe both are physically larger than the puny B400 OEM. I'm not sure if the TSB/recall will apply to your 2019 model, but it never hurts to ask, maybe contact SoA and open a case if your OEM has failed. Good luck! (y)
 
#68 ·
Well, I knew it was going to happen, but, like anyone else, I just didn't know when. Last night, in the garage, I went to start the Ascent. I put the foot on the brake and pressed the START button...then I heard some chattering and the lights started flickering, but the engine didn't want to turn over. I'm really surprised that our original OEM battery had lasted nearly 6 years. Sep 1, will be our 6th year of Ascent ownership. Last night, I went out to Wally World to buy an EverStart AGM Group 35 battery, but the store I went to didn't have any on the shelf. So, last night and this morning, I was perusing through the Ascent Forums looking for warranty and/or recommended battery replacement info from all of the other knowledgeable folks on this site. Later this morning, I called my dealership and talked to my favorite service advisor. She told me that if I can get it started and get it to her, it looks like it's covered under the Battery Drain settlement and they would replace it if the battery fails when they test it. This afternoon, I managed to get it started on the second push of the START button. I was so excited that it finally turned over without having to jump it. I got it to the dealership and they did their thing IAW the TSB 07-219-23. I got the new #SOA821B900 battery and all the applicable parts that make it fit right into the engine compartment. I have to say, today was a great day and I love my Subaru service department and I appreciate all of the great people that make this forum a wealth of knowledge as well as entertainment!
 
#71 ·
Good for you. I have a 2020 Ascent and as the weather is getting colder it is struggling to turn over if it sits more than a day. I have had it in to the dealership twice and asked them to test it, and they say it tests fine. Of course my dealership is an hour away so when I drive it there, it is fully charged up . It just seems to not be holding a charge as well as it used to. I don't have an alternate vehicle so I'm thinking about just pulling the trigger and replacing it myself. I could take it down and leave it with them overnight and they could run a more indepth test, but im not sure the loss of my time is worth it.
 
#73 ·
Am I the only one that’s thinks it’s nuts that Subaru has a TSB for a larger battery but continues to play the odds by installing the smaller battery in new vehicles on the production line?

The original TSB was released in 2022 and was updated in March 2024 to include the 2024 model year, yet my 2024 still has the smaller battery, which means Subaru isn’t using the larger batteries in production.
 
#89 ·
I just took my 2023 Ascent to the dealership in Leesburg, Fl to check the battery which I had to jump start twice this week. Unfortunately, since the Ascent had over 36,000 miles, a new $606 battery was installed. I was also informed that for an extra $300, the dealership would replace the Air and Cabin filters (both replaced six months ago) and wiper blades (replaced 3 weeks ago). I enjoy everything about the Subaru, except the expensive replacement parts on a two-year old vehicle.