2019 GMC Yukon Battery Size, Specs, and Replacement Guide

When you turn the key or press the start button on your 2019 GMC Yukon, you expect that massive V8 to roar to life without hesitation. As an ASE-certified master technician, I’ve seen my fair share of modern SUVs towed in simply because the battery wasn't up to the task of running all the onboard electronics.

Modern Yukons are incredibly power-hungry, and getting the exact right battery is critical to keeping the electrical system—and the battery management system (BMS)—happy.

Quick answer: 2019 GMC Yukon Battery Specs

For the 2019 GMC Yukon (both the 5.3L and 6.2L V8 engines, including Denali trims), here are the factory battery specifications you need to know:

• BCI Group Size: Group H6 (also known as Group 48) is standard. Vehicles with heavy-duty electrical systems or the 6.2L V8 Denali trim may use the slightly larger Group H7 (Group 94R).
• Cold Cranking Amps (CCA): 730 CCA minimum for H6 (Group 48); 800 to 850 CCA for H7 (Group 94R) applications.
• Reserve Capacity (RC): 120 to 140 minutes, depending on the exact group size and battery chemistry.
• AGM vs. Flooded: AGM (Absorbent Glass Mat) is highly recommended and often required as original equipment, especially for models equipped with heavy electrical loads, advanced infotainment, and start-stop technology.
• Terminal Layout: Top post, standard polarity (Right Positive).
• Physical Dimensions (H6/48): Approximately 10.9" L x 6.9" W x 7.5" H.
• Dual-Battery Setup: Not standard on the 2019 gas Yukon, though aftermarket kits or specific special-service packages may have provisions for a secondary auxiliary battery.

Replacement battery options

If you need a new battery for your 2019 GMC Yukon, sticking to premium AGM options is your best bet for longevity and reliability. Here are some of the most popular and reliable replacements:

1. ACDelco Gold AGM (Part # 48AGM or 94RAGM): The OEM replacement choice. Highly recommended to keep your Yukon matching factory spec perfectly.
2. Interstate MTZ AGM (Part # MTZ-48 H6): A top-tier battery offering massive deep-cycle capabilities and excellent warranties.
3. DieHard Platinum AGM (Group H6/48 or H7/94R): Famous for reliable cold-weather starting and vibration resistance.
4. Optima YellowTop (Part # DH6): A high-performance AGM option for those running aftermarket audio systems, winches, or auxiliary lighting.
5. Odyssey Performance Series (Part # ODP-AGM48 H6 L3): Military-grade construction providing some of the highest CCA and reserve capacities in its class.

AGM vs flooded — which does this vehicle need?

While some lower-trim Yukons originally came with standard flooded lead-acid batteries, upgrading to or maintaining an AGM (Absorbent Glass Mat) battery is highly recommended for the 2019 model year.

Modern GMC SUVs feature a complex Battery Management System (BMS), high-draw infotainment centers, heated/ventilated seats, power liftgates, and multiple computer modules that draw power even when the vehicle is off. AGM batteries charge up to five times faster, last up to twice as long, and handle deep discharging far better than conventional flooded batteries. If your Yukon came with an AGM battery from the factory, you must replace it with an AGM battery to avoid overcharging and early failure.

Post-installation relearn / reset procedure

Simply dropping a new battery into a 2019 Yukon isn't the end of the job. This vehicle uses a Battery Sensor Module on the negative battery cable to monitor the battery's state of charge and age. When you install a new battery, the system needs to be reset so the alternator adjusts its charging voltage appropriately.

To perform the relearn procedure:

1. Scan Tool Method (Preferred): Use an advanced OBD2 diagnostic scan tool. Navigate to the Body Control Module (BCM) or Engine Control Module (ECM) and select the "Battery Sensor Module Learn" or "Battery Age Reset" function.
2. Manual Relearn Method: If you don't have a bi-directional scan tool, you can allow the vehicle to relearn the battery state of charge naturally. Install the new battery, ensure all accessories and lights are completely off, lock the doors, and let the vehicle sit entirely undisturbed for at least 4 to 8 hours (overnight is best). The BMS will read the resting voltage and calibrate itself to the new battery.

Signs of a failing battery

Look out for these symptoms before you end up stranded:

• Slow or sluggish engine cranking, especially on cold mornings.
• The "Battery" or "Service Battery Charging System" light illuminates on the dash.
• Electrical gremlins (e.g., the infotainment screen resets, power running boards deploy slowly, or memory seats fail to move).
• Start-stop functionality stops working (the system disables itself when battery voltage drops to preserve starting power).
• Corrosion buildup on the battery terminals or a swollen battery case.

Common battery issues for this generation

The 2015-2020 generation of GM full-size SUVs (including the Yukon, Tahoe, and Escalade) is notorious for parasitic battery drains. The most common culprits include software glitches in the infotainment system keeping the modules awake, and faulty sensors (like door latch switches) preventing the vehicle from "going to sleep" when turned off. Furthermore, poor connections at the negative battery cable (which houses the current sensor) can cause false "low battery" warnings and erratic charging.

If your new battery drains quickly, have a technician perform a parasitic draw test to ensure your modules are shutting down properly.

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