2025 Subaru Outback Battery Size & Specs

Quick answer

• BCI group size: Group 35
• Cold cranking amps (CCA): 390 CCA
• Reserve capacity (RC): 100 minutes
• AGM vs flooded: AGM required
• Terminal layout: Left-hand positive
• Physical dimensions: 9 1/16" L x 6 7/8" W x 8 7/8" H (230mm x 175mm x 225mm)

Replacement battery options

• Interstate: MTX-35
• DieHard: Platinum AGM 35
• Optima: YellowTop DH6
• Odyssey: ODP-AGM35
• ACDelco: 35AGM

AGM vs flooded — which does this vehicle need?

The 2025 Subaru Outback requires an absorbed glass mat (AGM) battery. The Outback's charging system is designed for the specific voltage requirements of AGM batteries, and its extensive electronics and start-stop system rely on the stable power and deep-cycling capability that an AGM battery provides. Using a conventional flooded battery can lead to electrical gremlins, a shorter battery lifespan, and potential damage to the vehicle's charging system.

Post-installation relearn / reset procedure

After replacing the battery in a 2025 Subaru Outback, a relearn procedure is necessary to ensure all vehicle systems operate correctly. The primary system that needs to be reset is the power window auto up/down feature. To do this, go to each window and perform the following:

1. Lower the window completely.
2. Raise the window completely and hold the switch in the "up" position for one second.

No other major relearn procedures are typically required. The engine control module (ECM) will relearn the engine's idle and fuel trim characteristics over the first few drive cycles.

Signs of a failing battery

• Slow engine crank: The engine turns over more slowly than usual when you try to start it.
• Warning lights: The battery light or a "check charging system" message may appear on the dashboard.
• Dim lights: The headlights and interior lights may be noticeably dimmer than usual, especially during startup.
• Electrical issues: You may experience problems with the radio, navigation system, or other electronics.
• Visible corrosion: A white or bluish powder around the battery terminals is a sign of leaking battery acid.

Common battery issues for this generation

The most common battery-related issue for recent-generation Subaru Outbacks is premature battery failure due to the high electrical demands of the vehicle. The factory-installed battery can sometimes struggle to keep up with the power requirements of the extensive electronics, especially if the vehicle is used for frequent short trips where the battery doesn't have a chance to fully recharge. Upgrading to a high-quality aftermarket AGM battery can often resolve these issues.

Find a trusted shop on Repairius.