Diehard Vs Duralast Batteries- Key Differences With Tested Data

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Diehard and Duralast car batteries come from the same brand and are practically quite identical while creating the same hype. When seeking the best car battery for efficient engine start-up, you must know the difference between Diehard vs Duralast batteries to decide smartly.

The main difference between Diehard vs Duralast batteries is that the Diehard battery has more cranking amps. Conversely, the Duralast has more CCA, is charged more quicker, and handles heavy drains better.                                                                              

Read on to understand the difference between these two car batteries in all possible aspects, along with real-tested data and the recommendation.

Diehard vs Duralast Batteries: In-Depth Comparison

The car batteries that cost under $100 a couple of years ago now cost over $200 on average. Since car batteries get so expensive, you should pay for a battery that will last. The following comparison will let you decide the better choice between Diehard and Duralast:

Battery Type

Usually, two types of batteries are available on the market, and they are flooded lead-acid batteries and AGM, or absorbent glass mat, batteries.

The main difference between these two types of batteries is that the chemical components of the first type are spread openly around the battery, while the second type keeps them inside fiberglass mats.

Despite this, flooded lead-acid batteries are mainly used for old car models, while AGM batteries are found on new types of cars.

Both brands produce AGM and flooded lead-acid battery types. However, the flooded lead-acid batteries of Diehard offer more optimized performance, while the AGM batteries of Duralast are better performers than their counterparts.

Battery Variations

Diehard offers a large variety of car batteries compared to Duralast, which produces only two variations.

Some popular Diehard batteries are:

  • Diehard Platinum AGM
  • Diehard platinum
  • Diehard silver
  • Diehard gold
  • Diehard red

The variations of Duralast are

  • Duralast Gold
  • Duralast Platinum

Considering the number of variations, Diehard gets the edge.

Cranking Amps

The first test we’ll compare is the cranking amp test at 75 degrees Fahrenheit. Cranking amps are the total number of amps that a battery can generate at zero degrees Celsius. To perform this test, set the battery tester to CA mode to obtain cold cranking amps.

The batteries should have at zero degrees F so you can get an exact reading. A battery that holds a minimum of 1.2 volts per cell is considered a good battery.

Another piece of information you’ll find in this particular test is internal resistance. Internal resistance refers to how efficient a battery is at producing high currents. A new car battery should have an internal resistance of less than five.

In comparison, the Duralast battery made by Johnson Controls produces 12.8 volts and 1022 cranking amps with an internal resistance of 3.8. Conversely, this diehard battery is made by EnerSys and produces 13.04 volts in 1148 cranking amps with an internal resistance of 2.69. In terms of cranking amps, Diehard clearly gets the edge.

High Current Load

Next, you can perform this high current load test by powering up these two batteries for half an hour at between 42 and 44 amps of load using a converter. This way, you can understand the energy consumption, the voltage produced by these batteries, and their ability to handle a heavy drain. Remember, car batteries have 6 cells, and every cell is at 2.1 volts.

A car battery above 12.6 volts is considered as fully charged while 12.4 volts means it’s not fully charged. But anything below 12.4 volts means the battery needs to be recharged.

During the test, we found the Duralast was at 12.53 and the diehard at 12.49 volts. It means the Duralast retains the charge more strongly than the Diehard and can efficiently handle heavy drains.

Charging Speed Comparison

Some batteries charge more quickly than others. If you want to determine how fast these two car batteries charge, simply put a battery charger on these batteries for one hour applying the 10 amp setting along with the lower internal resistance.

After charging for one hour, we found a.28 amp improvement on the Duralst battery, which was.52 amp on the Diehard. Hence, we believe the Diehard-absorbed glass mat battery charges more quickly than the flooded lead acid batteries.

Cold-Cranking Amps

Cold-cranking amps, or CCA, refer to the capability of a car battery to start up an engine in colder weather. It’s a vital consideration for a car owner who lives in a cold region or needs to drive often in winter.

To perform this test, leave both batteries in a freezer for one day at zero degrees Fahrenheit. After a day, we found that the Duralast produced 753 cold-cranking amps while the diehard produced 697. So the Duralast produces the coldest cranking amps in cold weather, making it a better option for winter or cold climates.

Compared to at-27 degrees C or-20 degrees F for another 24 hours, we found the Duralast produced 708 cold cranking amps and the internal resistance was at 4.4. The Diehard battery, on the other hand, produced 580 cold-cranking amps with an internal resistance of 4.5 million ohms. It means Diehard may struggle to use it in frigid temperatures.

Reserve Capacity

Reserve capacity is the amount of time a car battery can generate 25 amps at 80 degrees Fahrenheit at a minimum voltage of 1.75 volts.

The reserve capacity of diehard batteries ranges from 140 to 90 minutes, which is 115 to 80 minutes for diehard batteries.

Diehard vs Duralast Batteries: Which Brand is the Best?

It depends on the type of battery you are using on your vehicle and some other considerations like budget and the temperature of the driving area.

So if your vehicle uses a flooded lead acid battery, continue using it, and these are less expensive as well. Likewise, if your vehicle has factory-equipped ABS glass mat batteries, continue using the same type. Even AGM batteries can handle vibration and deep discharge better as well as don’t require any maintenance. However, they cost a bit more.

And if you live in an area that doesn’t get below freezing, keep using Diehard, while Duralst is better for a colder environment.

Also Read: How To Read Abs Codes Without A Scanner?


1. What is the difference between DieHard gold and platinum batteries?

The main difference between DieHard gold and platinum batteries is that the gold one is an AGM battery and more affordable than the latter one. The DieHard gold is also more durable and ensures 60% increased electrical flow.

2. Which is better: Duralast gold or platinum?

The Duralast Platinum battery is more vibration resistant and carries double the deep cycle capacity of the Duralast Gold battery. The first model is also spill-proof and comes with a seal, making it the best for starting a vehicle and delivering all power demands.

3. Are Duralast and DieHard batteries the same?

Both the Duralast and DieHard batteries are produced by the same company and are available at AutoZone stores. However, they differ in type, cranking amps, CCA, and price.

Final Words

In this Diehard vs Duralast batteries comparison guide, we’ve compared both car batteries in possibly all the aspects, mentioning the real data-performing individual’s taste.  The result may vary depending on the type and model of car battery you choose from either side.

However, the overall final decision should be the same as we prefer. Lastly, you can experiment with these two types using their models and decide based on experience. 

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