2017 Subaru Outback Battery Size & Group

Quick Answer

• BCI Group Size: 25 or 35
• CCA Rating: 640 CCA minimum recommended (may vary slightly by OEM/trim)
• Reserve Capacity: 100-110 minutes minimum recommended
• AGM vs. Flooded: Either is generally acceptable, but AGM offers performance benefits.
• Terminal Layout: Top post, typically positive on the right (JIS terminal type).
• Physical Dimensions: (Group 25) 9.06" L x 6.81" W x 8.86" H; (Group 35) 9.06" L x 6.81" W x 8.86" H.
• Dual-Battery Setup: Not applicable; the 2017 Subaru Outback uses a single battery.

Replacement Battery Options

When it's time to replace the battery in your 2017 Subaru Outback, several reputable brands offer excellent choices. Always double-check the BCI group size and CCA rating to ensure compatibility.

• Interstate: MT-25 (Group 25) or MT-35 (Group 35)
• Optima: YellowTop DS46B24R (Group 35, AGM) or RedTop 35 (Group 35, AGM)
• DieHard: Platinum AGM Group 35 or Gold Group 35
• Odyssey: 35-PC1400 (Group 35, AGM)
• ACDelco: Advantage 35AGM (Group 35, AGM) or Professional 25 or 35 (Flooded)

AGM vs. Flooded — Which Does This Vehicle Need?

The 2017 Subaru Outback was originally equipped with a traditional flooded lead-acid battery from the factory. While a flooded battery is perfectly adequate for this vehicle, an Absorbent Glass Mat (AGM) battery offers several advantages that make it a worthwhile upgrade.

AGM batteries are sealed, spill-proof, and maintenance-free. They are also more resistant to vibration and can withstand deeper discharges without damage, leading to a longer lifespan in many cases. Due to their lower internal resistance, AGM batteries can also deliver more consistent power and recharge faster. Given that modern vehicles like the Outback have increasing electrical demands from infotainment systems, safety features, and various sensors, an AGM battery can provide more stable voltage delivery and handle parasitic draws more effectively. There is no specific requirement for an AGM battery in the 2017 Outback, but its enhanced performance and durability make it an excellent choice for those seeking a more robust battery solution.

Post-Installation Relearn / Reset Procedure

After disconnecting and replacing the battery in your 2017 Subaru Outback, you may notice some initial changes in vehicle behavior. The vehicle's computer (ECU) may lose some of its learned parameters, which can affect things like idle speed, shift points, and even power window operation. Fortunately, most of these issues will resolve themselves as the car "relearns" operating conditions over typical driving cycles.

Here are some common items that might need attention or will relearn:

• Idle Relearn: The engine idle may be a little rough or higher than usual initially. Drive the vehicle for a few cycles (short trips with engine on/off) and the idle should stabilize.
• Radio Presets: You will need to reset your radio stations.
• Clock: The clock will need to be reset.
• Power Windows: Sometimes, the auto up/down feature for the power windows may not work correctly immediately. To reset, roll each window down completely, then hold the button as you roll it up completely, continuing to hold it for a few seconds once it