2018 Freightliner M2 106 Battery Size & Group

Quick Answer

• BCI Group Size: Generally Group 31 (commercial heavy-duty)
• CCA Rating: 925-1000 CCA per battery (typically two to four batteries)
• Reserve Capacity: 180-200 minutes per battery
• AGM vs. Flooded: Flooded lead-acid is standard, but AGM is an excellent upgrade for longevity and deep-cycle tolerance.
• Terminal Layout: Typically SAE post, top terminal.
• Physical Dimensions: (Group 31) Approximately 13" L x 6.81" W x 9.44" H
• Dual-Battery Setup: The 2018 Freightliner M2 106 typically uses a multi-battery setup, often two, three, or even four Group 31 batteries connected in parallel for increased cranking power and reserve capacity, especially for diesel applications.

Replacement Battery Options

When it's time to replace the batteries in your 2018 Freightliner M2 106, you'll want to stick with high-quality, heavy-duty options designed for commercial use. Here are some popular choices:

• Interstate: MT31 (Flooded), MTD31 (Deep Cycle, good for auxiliary power), SRM-31 (AGM Deep Cycle)
• Optima: Optima Red Top 31 (Starting), Optima Yellow Top 31 (Deep Cycle/Starting - good for accessories)
• DieHard: Platinum Group 31 (AGM)
• Odyssey: 31-PC2150S (AGM, high CCA/RC)
• ACDelco: 31PHD (Flooded Heavy Duty)

(Note: Part numbers can vary by retailer and specific battery features. Always confirm with your supplier.)

AGM vs. Flooded — Which Does This Vehicle Need?

The 2018 Freightliner M2 106 originally came equipped with flooded lead-acid batteries. These are a cost-effective and reliable choice for most applications. However, AGM (Absorbent Glass Mat) batteries offer several advantages that make them a worthy upgrade, especially for a commercial vehicle:

• Durability: AGM batteries are more vibration resistant, which is crucial for heavy-duty trucks.
• Maintenance-Free: No need to check water levels.
• Slower Self-Discharge: They hold a charge longer when the truck is not in use.
• Better Deep Cycle Performance: If your truck has auxiliary power demands (e.g., liftgates, APUs, extensive interior lighting when parked), AGM batteries are better suited to handle repeated deep discharges without significant capacity loss.
• Faster Recharging: AGMs accept a charge more quickly.

While not strictly "needed," an upgrade to AGM can provide increased reliability and longevity, potentially offsetting the higher upfront cost in the long run.

Post-Installation Relearn / Reset Procedure

After replacing the batteries in your 2018 Freightliner M2 106, a "relearn" or "reset" procedure is generally not required for the engine control unit (ECU) in the same way it might be for some passenger cars. However, you may need to address a few minor items:

1. Radio/Infotainment System: You might lose saved radio presets. Some systems may require a security code to reactivate, so ensure you have this on hand if applicable to your specific head unit.
2. Clock: The clock will likely need to be reset.
3. Power Windows (if applicable): Some Freightliners with power windows might need a quick re-initialization. Typically, this involves holding the window switch down until the window is fully open, then holding it up until it