Why won’t my 911 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’ve been leaving the doors slightly open and the dome lights on during the night. Stop in for a free battery check at your local Firestone Complete Auto Care to learn more about the state of your battery.

What happens to my old 911 battery?

We’ll recycle your car battery for you!

How much do DieHard batteries cost for your Porsche 911?

Get affordable prices on Porsche 911 batteries by using one of our limited-time battery deals. Plus, all DieHard car batteries come with a free replacement warranty and extra coverage with DieHard Assurance.

How long can I expect my car battery to last?

A car battery normally lasts three to five years, but this number can vary based on battery type, your driving habits, and battery maintenance.

Why is there white, crusty buildup on my 911’s battery post?

The white, crusty stuff that can accumulate around 911 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 911 vehicle battery?

Regularly inspecting and cleaning your battery terminals will help keep your 911’s electrical system running smoothly. Before cleaning, reference your owner’s manual for instructions on how to disconnect the battery cables. Once the cables have been disconnected, gently clean the terminals with a mixture of water and baking soda, a wire brush, and a rag.

Where can I purchase 911 batteries near me?

When you need a new battery for your vehicle, Firestone Complete Auto Care is here to help. We sell and install 911 batteries at our stores nationwide — and our Firestone Direct mobile vans can provide convenient on-site battery services. Learn more about our mobile battery services and book an appointment.

2005 Porsche 911 Car Batteries

Get a New Porsche Battery

Get a New Porsche 911 Battery

Don't let a failing battery slow you down. Shop replacement batteries for 2005 Porsche 911s today and schedule a quick installation at Firestone Complete Auto Care.

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2005 Porsche 911 Battery Replacement & Size

Not sure what battery to get for your Porsche 911? Check the chart to find the right car battery size and cold cranking amps for your 911.

Battery	Engine	Warranty		Cold Cranking Amps
94RH7	H6/3.6L	Replacement 36 months	Performance months	800
H7-AGM	H6/3.6L	Replacement 36 months	Performance months	850
94RH7	H6/3.8L	Replacement 36 months	Performance months	800
H7-AGM	H6/3.8L	Replacement 36 months	Performance months	850

BATTERIES
H6/3.6L - Battery: 94RH7 - Warranty: Replacement 36 months, Performance months - Cold Cranking Amps: 800
H6/3.6L - Battery: H7-AGM - Warranty: Replacement 36 months, Performance months - Cold Cranking Amps: 850
H6/3.8L - Battery: 94RH7 - Warranty: Replacement 36 months, Performance months - Cold Cranking Amps: 800
H6/3.8L - Battery: H7-AGM - Warranty: Replacement 36 months, Performance months - Cold Cranking Amps: 850

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Buying a Replacement Battery for Porsche 911

Sadly, your Porsche 911 won't last forever. Neither will its battery. The average car battery lasts three to five years. You want to replace your 2005 Porsche 911 battery before it fails and leaves you stranded. Pay attention to clues that your battery is on its way out. A lagging starter, an illuminated check engine light or battery signal, swollen battery case, corrosion-covered posts, or dim headlights can all be signs that your battery needs attention.

Or, you can get a complimentary battery check at your nearest Firestone Complete Auto Care. With best-in-class tools we can tell you how much "life" is left in your battery. Drop in for a free battery check and, if necessary, a battery replacement to help keep your 2005 Porsche 911 running! Car batteries are only one of our many strong suits. Our technicians are well-acquainted with Porsche’s service specs for 911 battery cold cranking amps and reserve capacity. Get help identifying the type and size of battery that matches your vehicle, and schedule an appointment today for a quick car battery replacement.

Why Choose a DieHard Battery for Your 911?

We only want what’s best for your Porsche 911, which is why we only carry top-of-the-line replacement parts and batteries. Your 911 needs a reliable, durable and powerful battery in even some of the toughest conditions. DieHard batteries go above and beyond using state-of-the-art advancements to fuel the increasing power requirements of modern vehicles They're no ordinary battery, they're extraordinary. Buy a DieHard battery for your Porsche 911 and get behind the wheel with confidence. Why? Because your battery will perform when you need it. That's the kind of battery we deliver.

Making Your 911’s New Battery Last

Have you recently had a fresh battery installed in your Porsche 911? Congrats! You can give your new battery a head start with proper care and attention. You can take care of your battery by cutting back on unnecessary short trips, cleaning your battery posts, and not using electronics such as the radio and power outlets when the engine is off.

Answers to Your 911 Car Battery Questions

Firestone Complete Auto Care has answers to your top car battery questions. If you have a 911-specific battery question, pay us a visit. Our technicians have the answers.

Why won’t my 911 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’ve been leaving the doors slightly open and the dome lights on during the night. Stop in for a free battery check at your local Firestone Complete Auto Care to learn more about the state of your battery.
What happens to my old 911 battery? We’ll recycle your car battery for you!
How much do DieHard batteries cost for your Porsche 911? Get affordable prices on Porsche 911 batteries by using one of our limited-time battery deals. Plus, all DieHard car batteries come with a free replacement warranty and extra coverage with DieHard Assurance.
How long can I expect my car battery to last? A car battery normally lasts three to five years, but this number can vary based on battery type, your driving habits, and battery maintenance.
Why is there white, crusty buildup on my 911’s battery post? The white, crusty stuff that can accumulate around 911 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 911 vehicle battery? Regularly inspecting and cleaning your battery terminals will help keep your 911’s electrical system running smoothly. Before cleaning, reference your owner’s manual for instructions on how to disconnect the battery cables. Once the cables have been disconnected, gently clean the terminals with a mixture of water and baking soda, a wire brush, and a rag.
Where can I purchase 911 batteries near me? When you need a new battery for your vehicle, Firestone Complete Auto Care is here to help. We sell and install 911 batteries at our stores nationwide — and our Firestone Direct mobile vans can provide convenient on-site battery services. Learn more about our mobile battery services and book an appointment.