What battery goes in a 2018 Subaru Forester?
The 2018 Subaru Forester uses a standard 12-volt automotive battery, with Group Size 35 being the most common replacement. Some replacements may be listed as Group Size 34R depending on terminal orientation, so it’s crucial to verify the exact size on your current battery or in the owner's manual.
Understanding the battery choice for your Forester
Choosing the right battery involves confirming the correct group size, the electrical needs of the vehicle, and the local climate. While Subaru’s base Forester models rely on a conventional 12-volt lead-acid battery, variations in trim, regional specs, and aftermarket options can influence which battery fits best. Start with the original equipment specifications and then consider upgrades if you have additional electrical loads or extreme weather conditions.
Battery type and capacity considerations
For most 2018 Forester models, a conventional flooded, 12-volt lead-acid battery is suitable. Some buyers opt for an AGM (absorbed glass mat) battery as an upgrade for reduced internal resistance and improved performance under heavy electrical demand, but it is not a factory requirement for non-hybrid Forester models. When replacing, aim for a battery that meets or exceeds the OEM electrical specs and fits the engine bay’s tray and clamps.
Common group sizes you may encounter
Before you buy, be aware of the two most likely group sizes that fit a 2018 Forester. The following options cover typical replacements you’ll see at retailers, but always confirm the exact fit for your vehicle.
- Group Size 35 — The standard replacement size for most 2018 Forester models. It fits the battery tray and clamp in most configurations and provides the expected CCA and capacity for cold starts.
- Group Size 34R — An alternative in some cases where the terminal arrangement requires a different orientation. Not every 2018 Forester will accommodate this size, so verify terminal positions and fitment before purchasing.
Most Forester owners will use Group Size 35 as the default choice, but always confirm the exact size from the existing battery label or Subaru’s official documentation.
Key specifications to check when buying a replacement
When selecting a battery, these specs ensure reliable starts and proper compatibility with your vehicle’s electrical system, especially in colder climates or with extra electrical loads.
- Cold Cranking Amps (CCA): Look for a rating that meets or exceeds Subaru’s recommendation for your climate. Typical ranges for this vehicle fall around 450–600 CCA, depending on climate and usage.
- Reserve Capacity (RC): A higher RC helps maintain electrical system operation during charging issues. Aim for roughly 90–120 minutes or more, depending on how aggressively you use electrical accessories.
- Battery type: Conventional flooded lead-acid is standard; AGM is available as an upgrade option for higher vibration resistance or heavy electrical loads, but is not required for the 2018 Forester.
- Terminal layout and physical fit: Ensure the battery’s dimensions and terminal locations match your car’s tray, hold-down clamp, and cable routing. Confirm the polarity (positive/negative) aligns with your wiring to avoid misconnection.
Choosing a battery that matches these specs helps prevent fitment issues and ensures reliable starts in all seasons.
Tips for installation and care
Always observe basic safety when handling car batteries: wear eye protection, disconnect the negative terminal first, then the positive, and avoid short-circuiting. Clean corrosion from the terminals, apply terminal grease or dielectric spray, and re-tighten clamps to the manufacturer’s recommended torque. After installation, perform a quick voltage check and, if possible, a loading test to confirm the battery is delivering adequate performance.
Summary
The 2018 Subaru Forester generally uses a 12-volt lead-acid battery with Group Size 35 as the standard replacement. Some markets or dealer inventories may list Group Size 34R due to terminal orientation. When shopping, prioritize a battery with sufficient CCA for your climate (typically 450–600 CCA), adequate reserve capacity (about 90–120 minutes), and a proper physical fit for the tray and terminal layout. If your electrical demand is unusually high or you frequently park in extreme cold, consider an AGM option, but verify compatibility with your specific Forester model. Always verify the exact specifications on the battery you replace and consult the owner’s manual or Subaru parts catalog for the official recommendation.
What kind of battery does a Subaru Forester need?
A Subaru Forester needs a Group 35 battery, with newer models (2019+) requiring an AGM or EFB (Enhanced Flooded Battery) type due to features like start/stop technology. The specific requirements can vary by model year and trim, so it is best to confirm the exact battery specifications by checking the owner's manual or the label on the current battery.
Key specifications
- Group Size: Group 35 is standard for most models, though some specific trims or years might use a different size like Group 24F.
- Battery Type:
- 2019 and newer: An AGM (Absorbed Glass Mat) or EFB battery is recommended, especially for models with start/stop technology.
- Older models: A traditional flooded battery may be sufficient, but a modern AGM battery will also work and may offer longer life.
- Cold Cranking Amps (CCA): A minimum of 550 CCA is a good benchmark, with many recommended replacements having 650 CCA or higher.
How to find the right battery
- Check your owner's manual: This is the most reliable source for your vehicle's specific requirements.
- Look at the old battery: The label on the current battery will have its group size and other specifications.
- Use an online fitment guide: Websites for auto parts stores will have a "find the right battery" tool where you can enter your vehicle's year, make, and model to see compatible options.
What Batteries do subarus use?
- Duralast Platinum Group Size 35 EFB Battery 35-EFB.
- Duralast Platinum Group Size 47 H5 EFB Battery H5-EFB.
- Duralast Gold Group Size 24F Battery 24F-DLG.
- Duralast Gold Group Size 35 Battery 35-DLG.
- Duralast Gold Group Size 24 Battery 24-DLG.
- Duralast Gold Group Size 140R H4 Battery H4-DLG.
- Duralast Group Size 85 Battery 85-DL.
How long does a 2018 Subaru Forester battery last?
between 3-5 years
2018 Subaru Forester batteries usually last between 3-5 years, but this is variable depending on the type of battery, weather conditions, driving habits, and more. You can prolong the life of your Forester battery by: Keeping your vehicle stored indoors away from extreme swings in temperature or climate.
What kind of battery do I need for my 2018 Subaru Forester?
Duralast Platinum Group Size 35 EFB Battery 35-EFB
- PRICE: 179.99.
- Voltage: 12VDC.
- Length: 6.75in.
- Amp Hour Capacity at 20 Hours: 65Ah.
- Reserve Capacity Minutes at 25 Amp Load: 100min.
- Battery Type: Automotive.
- Reserve Capacity: 100min.
- BCI Group Size: 35.
