GarageDex

2003 Hummer H2 Battery Size

The 2003 Hummer H2 uses a BCI Group 79 battery, rated about 770-875 cold cranking amps (Flooded).

BCI Group Size79The case-size code that sets the physical fit and terminal layout.Verified fit
Battery type (OEM)
Flooded
Cold cranking amps (CCA)
770-875
Terminal position
Standard-terminal layout
Dimensions (L×W×H)
230×179×186 mm
Location
Under the hood (engine bay)

Side-terminal heavy GM truck. Always confirm against your owner's manual or current battery label.

Verified fitLast checked
Sources: CarSpecs
It comes with a standard flooded battery. You can usually step up to an AGM in the same Group 79 for longer life, but it isn't required. The 770-875 CCA rating is on the higher end, typical of larger engines and trucks, and it matters most for reliable cold-weather starts. Group 79 defines the case size and terminal layout (standard-terminal layout), so any reputable Group 79 battery will fit the tray and connect correctly.

Where to buy a Group 79 battery

A car battery is heavy and expensive to ship, so buying in person (Walmart, Costco, or a local auto-parts store) often beats online once you count free installation and the core-charge refund on your old battery. To compare prices and reviews online:

Search Group 79 batteries on Amazon770+ CCA, Flooded

As an Amazon Associate we earn from qualifying purchases, at no extra cost to you.

Frequently asked

What size battery does a 2003 Hummer H2 take?

The 2003 Hummer H2 uses a BCI Group 79 battery, rated around 770-875 cold cranking amps.

Does the 2003 Hummer H2 need an AGM battery?

No - it comes with a flooded battery from the factory. You can usually upgrade to AGM in the same Group 79 size, but it isn't required.

How many cold cranking amps (CCA) does it need?

Aim for roughly 770-875 CCA. Choosing at or above the OEM rating is fine; going below can cause hard starts in cold weather.

Where is the battery located?

Under the hood (engine bay). Standard-terminal layout.

Other vehicles that use Group 79

See all cars that take a Group 79 battery →
2007 Hummer H22006 Hummer H22005 Hummer H22004 Hummer H2

Also check the wiper sizes for your 2003 Hummer H2 →