2022 Subaru Outback Battery Size & Replacement Guide

As an ASE-certified master technician, I regularly see late-model Subaru vehicles in the bay for battery-related concerns. The 2022 Subaru Outback, part of the sixth generation, features a robust array of electronics, including the EyeSight driver assist system and an Auto Start-Stop system. These demands mean you can’t just drop any standard battery under the hood and expect it to last.

Here is the comprehensive guide to the battery specifications, replacement options, and reset procedures for your 2022 Subaru Outback.

Quick answer: 2022 Subaru Outback Battery Specs

Depending on your engine (2.5L naturally aspirated vs. 2.4L turbocharged) and trim, the Outback utilizes a couple of different sizes, but they all share high power requirements.

• BCI Group Size: Group 47 (H5) for most 2.5L models; Group 48 (H6) is often found in the 2.4L Turbo (XT / Wilderness) models. Always verify the physical size currently in your tray.
• Cold Cranking Amps (CCA): 600–650 CCA minimum for H5/47; 700–760 CCA minimum for H6/48.
• Reserve Capacity (RC): 100 to 120 minutes, essential for supporting electronics when the engine shuts off at stoplights.
• AGM vs Flooded Requirement: Subaru uses an Enhanced Flooded Battery (EFB) from the factory to handle the Auto Start-Stop system. However, upgrading to an Absorbed Glass Mat (AGM) battery is highly recommended for replacements.
• Terminal Layout: Standard Top Post.
• Physical Dimensions:
  • Group 47 (H5): Approx. 9.5" L x 6.9" W x 7.5" H
  • Group 48 (H6): Approx. 11.0" L x 6.9" W x 7.5" H
• Dual-Battery Setup: Not applicable to this vehicle (single 12V system).

Replacement battery options

If you are looking for reliable aftermarket replacements that meet or exceed OEM specifications, here are some top-tier choices. Note: Verify your specific group size (47/H5 or 48/H6) before purchasing.

• DieHard Platinum AGM (Group 47/H5 or 48/H6): An excellent direct-fit AGM that easily handles the repetitive cycling of the Outback's Auto Start-Stop system.
• Interstate MTX Series AGM (MTX-47/H5 or MTX-48/H6): Provides superior cranking power and a high reserve capacity for extreme weather.
• Optima YellowTop (DH5 or DH6): A premium AGM deep-cycle battery with vibration resistance, perfect for Outback Wilderness owners venturing off-road.
• Odyssey Performance Series (ODP-AGM47 H5 L2 or ODP-AGM48 H6 L3): Renowned for its massive plates and extreme longevity.

AGM vs flooded — which does this vehicle need?

The 2022 Subaru Outback comes from the factory with an EFB (Enhanced Flooded Battery) specifically to handle the heavy electrical loads of the Auto Start-Stop system. A standard, traditional flooded lead-acid battery will fail prematurely in this vehicle because it is not designed to be discharged and recharged constantly while sitting at traffic lights.

When it comes time to replace the original battery, you should only install an EFB or an AGM battery. An AGM battery is generally the superior choice; it is spill-proof, charges faster, and handles deep-cycle demands significantly better than any flooded counterpart.

Post-installation relearn / reset procedure

Swapping the battery on a 2022 Subaru Outback isn't just a physical job; the vehicle's computers need to adjust to the new power source.

1. BMS Reset: The Battery Management System needs to know a new battery was installed so it can adjust its charging alternator output. This usually requires a bi-directional scan tool. If you skip this, the alternator may overcharge the new battery, shortening its life.
2. Auto Up/Down Windows: After restoring power, your automatic windows may not work. Roll the driver’s window all the way down and hold the switch for 3-5 seconds. Then roll it all the way up and hold the switch for 3-5 seconds. Repeat for other affected windows.
3. EyeSight & Infotainment: You may notice the infotainment screen takes longer to boot up the first time, and the EyeSight system might take a short drive to recalibrate fully. Let the vehicle idle for about 5 minutes before driving.

Signs of a failing battery

• Auto Start-Stop stops working: The vehicle's computer will automatically disable the start-stop system if it detects battery voltage is too low to guarantee a restart.
• Sluggish cranking: The engine takes noticeably longer to turn over, especially on cold mornings.
• Flickering lights/screens: The massive 11.6-inch infotainment screen may flicker, reboot, or glitch out during engine cranking.
• Dashboard warnings: The check engine light, ABS, and EyeSight lights may illuminate simultaneously due to low voltage triggering sensor faults.

Common battery issues for this generation

The sixth-generation Subaru Outback (2020+) is notorious for parasitic power draws. The combination of the Starlink telematics system constantly searching for a cellular signal and the complex keyless access system can drain a battery if the car sits unused for a week or more. Furthermore, the OEM EFB batteries have a reputation for failing just outside of the 3-year warranty window. Upgrading to a high-quality AGM battery and keeping the vehicle on a smart trickle charger during extended periods of inactivity will save you a lot of headaches.

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