2019 Isuzu NPR Battery Size & Group

Quick answer

• BCI Group Size: Group 31 (commercial heavy-duty)
• CCA Rating: 925 CCA minimum per battery
• Reserve Capacity: 180-200 minutes per battery
• AGM vs. Flooded Requirement: Flooded (lead-acid) starting batteries are standard. AGM is an upgrade but not generally required.
• Terminal Layout: Typically top post, SAE terminals.
• Physical Dimensions: Approximately 13" L x 6.8" W x 9.4" H per battery.
• Dual-Battery Setup: Yes, the 2019 Isuzu NPR utilizes a dual-battery setup (2x Group 31).

Replacement battery options

When it's time to replace the batteries in your 2019 Isuzu NPR, you'll want to stick with a reliable Group 31 commercial deep cycle or starting battery, depending on your vehicle's specific configuration and accessory load. Here are some popular options:

• Interstate: Commercial batteries (e.g., MTZ-31, 31-MHD)
• Optima: Optima batteries are not typically recommended for the heavy-duty starting requirements of a commercial truck like the NPR due to their design for specific applications, though some RedTop Group 31 options exist.
• DieHard: DieHard Commercial batteries (e.g., DieHard Platinum Commercial Group 31)
• Odyssey: Odyssey Group 31 (e.g., ODY-31-PC2150S)
• ACDelco: ACDelco Professional Group 31 (e.g., 31-7YR)

Always verify the exact part number with your supplier as specifics can vary.

AGM vs. flooded — which does this vehicle need?

The 2019 Isuzu NPR primarily comes equipped with traditional flooded lead-acid batteries from the factory. These are perfectly adequate for the vehicle's starting and electrical demands. Flooded batteries are generally less expensive and perform well in a wide range of operating conditions.

Absorbent Glass Mat (AGM) batteries are an upgrade. They offer several advantages:

• Maintenance-free: No need to check electrolyte levels.
• Vibration resistance: Can better withstand the rigors of commercial truck operation.
• Improved cycling performance: Better for vehicles with significant accessory loads or frequent start-stop cycles.
• Lower self-discharge rate: Holds a charge longer when the vehicle is not in use.

While AGM batteries are superior in many aspects, they are also more expensive. For most NPR owners, sticking with a high-quality flooded Group 31 battery is a cost-effective and reliable choice. If your truck has extensive upfitting, auxiliary power needs, or operates in extreme conditions, then investing in AGM batteries might be beneficial.

Post-installation relearn / reset procedure

After replacing the batteries in your 2019 Isuzu NPR, it's a good practice to perform a basic reset, especially if you experience any unusual electrical behavior or warning lights. While Isuzu NPRs are generally straightforward, and a complex relearn isn't always required, these steps can help:

1. Ensure Proper Connection: Double-check that all battery terminals are clean, tight, and correctly connected (positive to positive, negative to negative).
2. Idle Relearn (if needed): After reconnecting the batteries, start the engine and let it run at idle for 5-10 minutes without touching the accelerator. This allows the engine control unit (ECU) to re-learn its idle parameters.
3. Check for Warning Lights: Monitor the dashboard for any persistent warning lights. If any remain, further diagnosis may be required.
4. Radio/Clock Settings: You will likely need to re-enter your radio presets and reset the clock.

For more complex issues or persistent electrical problems, consulting a professional Isuzu technician is recommended.

Signs of a failing battery

Commercial truck batteries, especially in a dual-battery setup, can show signs of failure in various ways:

• Slow Cranking: The engine turns over sluggishly, taking longer than usual to start.
• Dim Lights: Headlights or interior lights appear dim, especially when the engine is off or cranking.
• Warning Lights: A battery warning light or check engine light (sometimes triggered by low voltage) on the dashboard.
• Corrosion: Excessive corrosion around the battery terminals can indicate a poor connection or an expiring battery.
• Swollen Battery Case: A bulging or cracked battery case is a clear sign of internal damage and requires immediate replacement.
• Sulphuric Odor: A smell of rotten eggs can indicate the battery is overheating or overcharging.
• Electrical Gremlins: Unexplained electrical malfunctions, such as flickering lights or erratic accessory operation.

In a dual-battery system, one failing battery can put undue stress on the other, leading to premature failure of both. It's often recommended to replace both batteries in a dual setup simultaneously.

Common battery issues for this generation

Owners of 2019 Isuzu NPR trucks generally experience the typical issues associated with heavy-duty commercial vehicle batteries. Given their demanding work cycles, these trucks rely heavily on robust battery performance.

• Vibration Damage: Commercial trucks are subject to constant vibrations, which can loosen internal battery components over time, leading to premature failure. Using batteries designed for heavy-duty applications with reinforced cases is crucial.
• Parasitic Draw: Aftermarket accessories, telematics units, and even certain factory modules can develop a parasitic draw, slowly draining the batteries over time, especially when the vehicle is parked for extended periods. This can lead to frequent dead batteries.
• Sensing Wiring Issues: Problems with the battery sensing wire or associated charging system components can lead to improper charging, either undercharging (limiting battery life) or overcharging (damaging batteries).
• Corrosion: Due to exposure to dirt, moisture, and road salt, battery terminals and cables can corrode, increasing resistance and hindering proper charging and starting.
• Alternator Issues: A failing alternator will not properly charge the batteries, leading to repeated drain and eventual battery failure. It's important to ensure the charging system is functioning correctly when diagnosing battery problems.

Regular inspection of battery terminals, cables, and checking the charging system output are key to maximizing battery life in your Isuzu NPR.

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