2016 Subaru Outback Battery: Group Size, CCA & Replacement Guide

Quick Answer

• BCI Group Size: 25, 34R, or 35 (depending on trim and original equipment)
• CCA Rating: Typically 500-650 CCA
• Reserve Capacity: Approximately 90-120 minutes
• AGM vs. Flooded: Flooded (lead-acid) is standard; AGM is a viable upgrade.
• Terminal Layout: Top Post, typically A (positive on the left, negative on the right when looking at the battery from the front).
• Physical Dimensions: Varies slightly by group size, but generally fits within a 9" L x 7" W x 9" H envelope.
• Dual-Battery Setup: Not applicable (not a diesel).

Replacement Battery Options

Here are some popular replacement battery options for your 2016 Subaru Outback. Always verify the group size and specifications before purchase.

• Interstate: MT5-35, MTZ-35 (AGM option), MT5-25, MTZ-25 (AGM option)
• Optima: YellowTop D35, RedTop 35
• DieHard: Gold 35, Platinum 35 (AGM option)
• Odyssey: 35-PC1400
• ACDelco: 35AGM (AGM option), 35S

AGM vs. Flooded — Which Does This Vehicle Need?

The 2016 Subaru Outback typically comes factory-equipped with a conventional flooded lead-acid battery. This type of battery is perfectly adequate for the vehicle's electrical demands under normal operating conditions. Flooded batteries are generally more affordable and readily available.

However, an Absorbed Glass Mat (AGM) battery is an excellent upgrade option. AGM batteries offer several advantages:

• Improved Durability: They are more resistant to vibration and impacts, making them suitable for rough roads or off-road use.
• Slower Self-Discharge: They hold their charge longer when the vehicle is not in use.
• Better Performance in Extreme Temperatures: They tend to perform more consistently in both very cold and very hot weather.
• Maintenance-Free: No need to check or add distilled water.
• Better for Stop-Start Systems: While the 2016 Outback does not have a comprehensive stop-start system, vehicles with many accessories or frequent short trips can benefit from an AGM's deeper cycling capabilities.

While an AGM battery is not strictly "needed," it can provide enhanced reliability and longevity, especially if you live in an area with extreme temperatures or frequently use many electronic accessories.

Post-Installation Relearn / Reset Procedure

After replacing the battery in your 2016 Subaru Outback, it's important to be aware of potential procedures to ensure all systems function correctly. While a complex "relearn" procedure is not typically required for this generation of Outback, you might notice some minor anomalies that a simple reset can resolve.

1. Idle Relearn: The engine control module (ECM) may need to re-learn its idle parameters. After connecting the new battery, start the engine and let it idle for 10-15 minutes without touching the accelerator. This allows the ECM to adapt to its new voltage reference.
2. Window Auto-Up/Down: You might find that the automatic up/down function for your power windows (if equipped) doesn't work immediately. To reset this, roll each window all the way down, then all the way up, holding the switch in the "up" position for a few seconds after it closes.
3. Radio Presets & Clock: These will almost certainly be lost and will need to be reprogrammed manually.
4. Steering Angle Sensor (SAS): Although less common on the 2016 Outback, some vehicles may require the SAS to be recalibrated if warning lights related to stability control appear. This typically involves driving straight for a short distance or a more specific procedure that may require a scan tool. Consult your owner's manual if warning lights persist.

Important: Ensure all accessories (lights, radio, climate control) are off before disconnecting and connecting the battery to prevent potential electrical spikes.

Signs of a Failing Battery

Recognizing the signs of a dying battery can save you from being stranded. Look out for these common indicators:

• Slow Cranking: The engine turns over sluggishly when you try to start the car, especially in cold weather.
• Dim Headlights/Interior Lights: Lights appear dim when the engine is off but brighten when the engine is running.
• Warning Lights: A battery or charging system warning light illuminates on your dashboard.
• Corrosion: Excessive corrosion around the battery terminals can indicate a poor connection or an overcharging issue.
• Swollen Battery Case: If the battery case looks swollen or bulging, especially on the sides, it's a sign of internal damage and indicates immediate replacement is needed.
• Age: Most automotive batteries last 3-5 years. If yours is older, it's a good idea to have it tested.

Common Battery Issues for This Generation

While the 2016 Subaru Outback is generally reliable, like any vehicle, it can experience some battery-related issues common to its generation:

• Parasitic Draws: Sometimes, an electrical component (e.g., aftermarket accessories, faulty module, glove box light staying on) can draw a small amount of current even when the car is off, slowly draining the battery over time. If you frequently find a dead battery after leaving your car parked for a few days, a parasitic draw test may be necessary.
• Alternator Issues: While the battery stores power, the alternator generates it. A failing alternator won't adequately charge the battery, leading to repeated drain and eventual battery failure. Signs include a battery warning light, dimming lights while driving, or electrical accessory malfunctions.
• Terminal Corrosion: While normal aging can cause some corrosion, excessive build-up on battery terminals can prevent a good electrical connection, leading to starting problems. Regular cleaning and application of anti-corrosion spray can mitigate this.
• Original Equipment Battery Life: Factory batteries are often designed for cost-effectiveness, and some owners report shorter lifespans (closer to 3 years) compared to aftermarket replacements.

Find a trusted shop on Repairius.