For the 1998 Dodge Ram 2500, battery sizing depends on the engine type. Gasoline models typically use a single 12-volt Group 75 battery, while the Cummins 24V diesel variant uses two 12-volt batteries to provide a 24-volt starting system. Exact sizing can vary by trim and climate, so always verify against the battery label or the owner's manual.
Gasoline Ram 2500: common battery sizes
The following sizes are most commonly installed on gasoline-powered Ram 2500s from this era, with typical cold-cranking amp (CCA) ranges.
- Group 75 battery, about 650–750 CCA depending on climate and specific model.
- Alternative Group 24F battery in some configurations, typically around 600–750 CCA.
In practice, most 1998 Ram 2500 gasoline models used Group 75 as the standard replacement option, though Group 24F variants appeared in some configurations.
Cummins diesel Ram 2500: dual 12V batteries
Diesel-powered Rams from 1998 commonly employ two 12-volt batteries to support the 24-volt starting system. The exact group sizes can vary by vehicle, but two batteries of Group 24F or Group 31F are typical choices, each providing roughly 600–900 CCA depending on the model.
- Two 12-volt batteries wired to deliver 24 volts for starting, commonly Group 24F or Group 31F per battery.
- Each battery generally offers around 600–900 CCA, contributing to a higher overall cranking capacity.
Note: Always confirm the exact battery pairing and group size for your specific truck variant by inspecting the battery labels or consulting the service documentation.
How to confirm your exact battery size
To ensure you buy the correct replacement, use these verification steps.
- Check the under-hood label or the owner’s manual for the recommended group size (e.g., Group 75, 24F, or 31F).
- Look at the existing battery’s label for the “Group” designation and its CCA rating.
- Measure the battery tray dimensions to ensure a proper fit with the chosen group size.
- If you have the diesel, verify whether there are two batteries in place and their respective group sizes.
Conclusion: When replacing, choose a battery (or pair, for the diesel) that meets or exceeds the original CCA and reserve capacity requirements and fits the tray properly.
Summary
The 1998 Dodge Ram 2500 did not use a single universal battery size. Gasoline models typically use a single Group 75 12-volt battery, while the Cummins 24V diesel variant uses two 12-volt batteries (commonly Group 24F or 31F) to deliver 24-volt starting. Always verify with the battery label or the owner’s manual, and ensure the replacement matches or exceeds the original specifications for your climate and driving needs.
Is a group 27 battery bigger than a group 24?
Group 27 batteries are typical in size, but larger than Group 24 batteries. The dimensions are 12.5" L x 6.75" W x 9.37" H. These batteries are commonly used in RVs, boats, off-grid systems, and backup power systems.
What size battery is in the Dodge Ram Cummins?
Most newer RAM trucks will use either a DH7 or H8 battery.
What battery does a Ram 2500 use?
DieHard Platinum AGM – Battery : H7 Group Size, 850 CCA, 1000 CA, 140 Minute Reserve Capacity (Part No. H7-AGM)
What size battery is in a 1998 Dodge Ram?
Optima – Yellow Battery : Group Size 34/78DT, 750 CCA, 870 CA, 120 Minute Reserve Capacity, Deep-Cycle (Part No. D34/78-950)