Why won’t my S15 battery hold a charge?

A battery is in its final hour when it will no longer hold a charge. The battery might be old. Or, you may have a habit of leaving your car doors open and the dome lights on during the night. Stop in for a free battery check at your favorite Firestone Complete Auto Care and learn more about your battery's charge.

What happens to my old S15 battery?

We’ll recycle your car battery for you!

How much do DieHard batteries cost for your GMC S15?

GMC S15 batteries can be affordable, especially when there's an available battery coupon. The best part is every DieHard battery comes with a free replacement warranty and extra coverage with DieHard Assurance.

How long is a car battery good for?

The typical 12-volt car battery may last three to five years, depending on the type of battery, the driving conditions, and how well the battery is maintained.

Why is there white, flaky stuff around my S15’s battery post?

The white, crusty stuff that can accumulate around S15 car battery terminals is called corrosion. It is caused by a chemical reaction between the battery acid and the air, which creates a white, powdery substance that can build up on the terminals over time. Corrosion can interfere with the flow of electricity between the battery post and the car's electrical system, sometimes leading to poor electrical performance, difficulty starting, and even premature battery failure.

How do I clean corrosion off my S15 vehicle battery?

Regularly inspect the terminals and clean them with a mixture of baking soda and water, a wire brush, and a rag. Disconnect the battery cables before cleaning to help avoid the risk of electrical shock. Always reference and follow the instructions in your vehicle owner’s manual prior to disconnecting the battery cables.

Where can I find a battery for my S15?

Your local Firestone Complete Auto Care sells and installs S15 batteries in your neighborhood. Our Firestone Direct mobile vans can even come to you and do it! Learn more about mobile battery services.

1985 GMC S15 Batteries

Get a New GMC Battery

Get a New GMC S15 Battery

Don’t let a dead battery stop you. Shop replacement car batteries for your 1985 GMC S15 at Firestone Complete Auto Care.

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The Right Battery Size for a 1985 GMC S15

Not sure what battery to get for your GMC S15? Use this chart to find the right battery size and CCAs for your GMC S15.

Battery	Engine	Warranty		Cold Cranking Amps
78-1	L4/1.9L	Replacement 24 months	Performance months	700
75FT-3	L4/1.9L	Replacement 36 months	Performance months	700
78-AGM	L4/1.9L	Replacement 36 months	Performance months	740
34/78-4	L4/2.2L	Replacement 24 months	Performance months	800
78FT-2	L4/2.2L	Replacement 36 months	Performance months	800
78-1	L4/2.5L	Replacement 24 months	Performance months	700
78FT-2	L4/2.5L	Replacement 36 months	Performance months	800
78-AGM	L4/2.5L	Replacement 36 months	Performance months	740
34/78-4	V6/2.8L	Replacement 24 months	Performance months	800
78FT-2	V6/2.8L	Replacement 36 months	Performance months	800
78-AGM	V6/2.8L	Replacement 36 months	Performance months	740

BATTERIES
L4/1.9L - Battery: 78-1 - Warranty: Replacement 24 months, Performance months - Cold Cranking Amps: 700
L4/1.9L - Battery: 75FT-3 - Warranty: Replacement 36 months, Performance months - Cold Cranking Amps: 700
L4/1.9L - Battery: 78-AGM - Warranty: Replacement 36 months, Performance months - Cold Cranking Amps: 740
L4/2.2L - Battery: 34/78-4 - Warranty: Replacement 24 months, Performance months - Cold Cranking Amps: 800
L4/2.2L - Battery: 78FT-2 - Warranty: Replacement 36 months, Performance months - Cold Cranking Amps: 800
L4/2.5L - Battery: 78-1 - Warranty: Replacement 24 months, Performance months - Cold Cranking Amps: 700
L4/2.5L - Battery: 78FT-2 - Warranty: Replacement 36 months, Performance months - Cold Cranking Amps: 800
L4/2.5L - Battery: 78-AGM - Warranty: Replacement 36 months, Performance months - Cold Cranking Amps: 740
V6/2.8L - Battery: 34/78-4 - Warranty: Replacement 24 months, Performance months - Cold Cranking Amps: 800
V6/2.8L - Battery: 78FT-2 - Warranty: Replacement 36 months, Performance months - Cold Cranking Amps: 800
V6/2.8L - Battery: 78-AGM - Warranty: Replacement 36 months, Performance months - Cold Cranking Amps: 740

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Buying a Replacement Battery for GMC S15

Sadly, your GMC S15 won't last forever. Neither will its battery. On average, auto batteries last anywhere from three to five years. Check your battery regularly and replace it as needed so it doesn’t leave you and your GMC S15 stranded. Watch for signs that your current battery is getting too old or too weak. A slow engine crank, an illuminated battery or check engine light, swollen battery case, corroded battery terminals, or dim headlights can all signal that your battery is waving goodbye.

Plus, at Firestone Complete Auto Care, we’ll test your battery for free. Our equipment can see how much charge is left in your battery. Drop in for a free battery check and, if needed, get your GMC S15 a replacement battery. Car batteries are one of our many specialties! Our technicians are well-acquainted with GMC’s service specs for S15 battery CCAs and reserve capacity. Get help identifying the type and size of battery that fits your car perfectly, and schedule an appointment today for a quick car battery replacement.

Firestone Has DieHard Batteries for S15s

We know what’s best for your GMC S15, which is why we carry just that. Your S15 needs a reliable, durable and powerful battery that can handle most extreme environments and weather conditions. DieHard batteries shatter expectations using state-of-the-art advancements to fuel the increasing power demands of modern vehicles Don't call a DieHard battery ordinary. It's an extraordinary battery. Choose a DieHard battery for your GMC S15 and drive with confidence knowing that performance will be there when you need it most. That's the kind of battery we deliver.

After Buying 1985 GMC S15 Battery

Have you recently had a fresh battery installed in your GMC S15? Congrats! Now, help it last longer and stay charged by caring for it from the get-go. turning off all of the lights when you leave your vehicle, limiting short trips, cleaning your battery posts, and not playing the radio or using other electronics when the engine is turned off.

Answers to Your S15 Car Battery Questions

Firestone Complete Auto Care has answers to your top car battery questions. If you have battery questions that are GMC S15-specific, stop by your nearest store. Our expert techs have the answers you need.

Why won’t my S15 battery hold a charge? A battery is in its final hour when it will no longer hold a charge. The battery might be old. Or, you may have a habit of leaving your car doors open and the dome lights on during the night. Stop in for a free battery check at your favorite Firestone Complete Auto Care and learn more about your battery's charge.
What happens to my old S15 battery? We’ll recycle your car battery for you!
How much do DieHard batteries cost for your GMC S15? GMC S15 batteries can be affordable, especially when there's an available battery coupon. The best part is every DieHard battery comes with a free replacement warranty and extra coverage with DieHard Assurance.
How long is a car battery good for? The typical 12-volt car battery may last three to five years, depending on the type of battery, the driving conditions, and how well the battery is maintained.
Why is there white, flaky stuff around my S15’s battery post? The white, crusty stuff that can accumulate around S15 car battery terminals is called corrosion. It is caused by a chemical reaction between the battery acid and the air, which creates a white, powdery substance that can build up on the terminals over time. Corrosion can interfere with the flow of electricity between the battery post and the car's electrical system, sometimes leading to poor electrical performance, difficulty starting, and even premature battery failure.
How do I clean corrosion off my S15 vehicle battery? Regularly inspect the terminals and clean them with a mixture of baking soda and water, a wire brush, and a rag. Disconnect the battery cables before cleaning to help avoid the risk of electrical shock. Always reference and follow the instructions in your vehicle owner’s manual prior to disconnecting the battery cables.
Where can I find a battery for my S15? Your local Firestone Complete Auto Care sells and installs S15 batteries in your neighborhood. Our Firestone Direct mobile vans can even come to you and do it! Learn more about mobile battery services.