You may have asked yourself: “Why does my Duramax have two alternators?” Well, you’re in the right place if you want to learn the answer to that question.

Let’s get to it.

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Why Does My Duramax Have Two Alternators?

The Duramax has two batteries, to help it start in cold weather. The two alternator option helps keep the batteries charged when using a lot of electrical power, such as snow plough, or tow truck operation. Both alternators work together as one large one.

Can You Have 2 Alternators?

If you have a dual-voltage alternator, then yes, you can have 2 alternators. There are no rules against having more than one.

The only issue is that the voltage regulators for each alternator need to be matched for the total output of your alternators. If your alternators are both 12 volts at 75 amps, then you will need 2 regulators that can handle a total of 150 amps.

If they are both 24v at 50 amps, then you will need 2 regulators that can handle a total of 100 amps.

And, if they are both 48v at 25 amps each, then you will need 2 regulators that can handle a total of 50 amps each.

Can You Run A Duramax On One Battery?

Yes, you can run a Duramax on one battery.

Many people have asked this question and the answer is yes, you can run a Duramax on one battery. However, there are some things to consider before doing so.

The first thing you need to do is make sure that the battery is in good condition. If it is not, get it replaced before trying to start the truck. Also, make sure that the alternator is working properly because if it isn’t then you will not be able to charge your battery while driving.

You will also want to make sure that your headlights are off while you are running on one battery because they will drain the battery quite quickly if left on for long periods of time.

How Many Amps Does It Take To Start A Duramax?

To start a Duramax, you need a minimum of 50 amps.

The Duramax engine has an alternator that produces up to 100 amps of current. This means that you can connect two batteries together in series (positive end to negative end) and it will produce enough current to start the engine.

The problem is that most people don’t have any more than one good battery and two in series would mean overcharging one battery (or not charging at all) while trying to start their truck.

The solution is to use a large deep cycle battery (one made for RVs or boats). These batteries are designed for long term storage of energy so they don’t mind being discharged completely every time they are used.

They also have much thicker plates inside them than car batteries do which gives them more amp hours and allows them to be discharged further without damage than car batteries can be.

If you put one of these large deep cycle batteries in parallel with your starter battery (positive end to positive end), you should have plenty of power available to start your vehicle.

Can You Jump Start A Duramax?

The Duramax is a 6.6L V-8 diesel engine used in GM vehicles. The Duramax can be jump-started, but only with a special jumper cable that has a resistor built into it. The resistor helps prevent damage to the vehicle’s computer system when jump-starting the Duramax.

The first step is to locate the battery terminals on both vehicles. The positive terminal will have a plus sign next to it and should be marked with a red wire on top of the terminal post. The negative terminal will have a minus sign next to it and should be marked with a black wire on top of the terminal post.

Next, you will need to find where the battery cables connect on your Duramax truck’s engine compartment or underhood area (this can vary depending on what year and model your vehicle is).

Once you have located these connections, disconnect them by turning them counterclockwise until they are free from their clips or retaining devices.

Now that both batteries are disconnected from each other, attach one end of your jump starter cables onto the positive connection on each vehicle’s battery (red wire for positive). Then connect the other end of these cables onto each other using another set of jump starter cables, which is connected directly.

How Do I Know If My Duramax Battery Is Bad?

Battery failure is one of the most common causes of a truck’s inability to start. When a battery fails, it can take out other electrical components as well.

A Duramax battery is made up of a group of lead plates and sulfuric acid in a glass mat container. Over time, these lead plates corrode and break down from chemical reactions that occur within the battery.

The best way to determine if your Duramax battery is bad is by performing a load test. The load test tells you how much electrical current it can supply under load conditions (starting). You can also take a voltage reading with a digital voltmeter but this doesn’t tell you how much power is available for starting purposes.

There are two ways to check for proper charging voltage:

You can check the voltage with an analogue voltmeter on the positive (red) wire at the starter solenoid or on the positive terminal of the battery itself. This should read between 13.8-14 volts when the key is turned on but not cranking.

If you have access to an oscilloscope or multimeter with frequency counter capability, you can also check for proper charging voltage at various points along with your charging system wiring harness.

How Long Do Duramax Batteries Last?

The answer is, “as long as you maintain them properly.”

If you are a truck owner and you have a Duramax engine, then you know just how important it is to keep your battery charged. You also know that if your Duramax battery dies, it could be a very costly fix. So it’s important to understand how long Duramax batteries last and how to take care of them so that they can last for years or decades.

How Long Does An Average Duramax Battery Last?

It depends on whether or not you maintain them properly. A well-maintained Duramax battery should last anywhere from four to eight years. If you don’t maintain your battery properly and don’t change the fluid regularly (or at all) then it will die much sooner than that.

Why Do Duramax Batteries Die?

Most Duramax batteries die because people don’t take proper care of them and don’t follow the manufacturer’s instructions on maintenance. This can lead to corrosion or other problems that shorten the life of your battery significantly over time.