Best Glow Plugs for Duramax – 2021 Reviews

| Last Updated: December 25, 2021

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If your vehicle is giving you a hard time and is not heating up properly, then it's certainly time to invest in good-quality Duramax Glow Plugs. These are specially designed to give engines the right amount of heat needed to accelerate the 'cold starts.'

They are also crucial in optimizing the throttle response of your cars and maintaining ignitions at all instances. But most vehicles come with these small pieces of machinery. The problem is the inclusion of cheaper and lower quality products. If you want to fix the heating delays, then you can look for a suitable Glow Plug set from our list.

The article also touches upon other important areas related to these plugs. Detailed sections have been allocated to discussing top features, installation, and FAQ. Make sure to give the article a quick read so you can make the wisest decision for your Duramax.

Comparison of the Best Glow Plugs For Duramax

  • Engine will quickly reach optimal temperatures
  • Allows faster engine startup
  • Provides high thermal conductivity
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  • Made to resist corrosion and vibration
  • Will run at lower temperatures
  • Good isolation and quality
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  • Best for the Money
  • Tested with high standards
  • Very easy to install on vehicle
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  • Best LBZ Duramax Glow Plug
  • Compatible with many different vehicles
  • Made from high-quality materials
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  • Best ACDelco Glow Plug for Duramax
  • Will improve engine startup
  • Controls electrical flow with self-regulation feature
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When is it Time to Replace My Glow Plugs?

This is one of the most important questions asked on the internet, and we thought we should end the confusion once and for all. When it comes to Glow Plugs, the lifespan isn’t usually the issue, as good quality products usually last for a very long time. Since these units heat incoming air and fuel and lead to efficient fuel combustion, it is only natural that extreme variations in the temperature and the surroundings will hamper their function.

Any rough starts or misfires can lead to your Glow Plugs getting defected and causing trouble, especially in cold weather. When you consistently have a hard time heating your vehicle or if you feel that your car is not working adequately in cold conditions, it is time to replace the Glow Plugs. Replacements tend to be cheap and easily available, so you don't have to worry about that too much.

How to Choose New Glow Plugs

Like with most other products, Glow Plugs also come in a range of shapes and sizes. To get your hands on the best possible product, you will have to keep a couple of things in mind. Here is how you choose your new Glow Plugs.


Cost is an important consideration because, in most instances, you will have to replace all eight of your Duramax Glow Plugs instead of only one. Most models are affordable and can be bought at less than $100. 

However, other variations require double the investment. The models with price ranging between $200 and $300 often tend to have a longer shelf life. You need to keep the labor costs in mind too, which range between $100 and $200.


You don't want to end up with a product that loses its potency soon and requires repairs and replacements. This is why you should always consider the brand name and the reputation of the company before investing. Most plugs will last for as long as 100,000 miles. They will gradually lose their efficiency, and you don't want this to happen sooner rather than later.


Since these units are essential to the safe and effective working of your vehicle, you must keep things like construction material and durability in mind. Wear and tear over a long period can seriously hamper the effectiveness and lead to faulty Glow Plugs. This could mean lower heat retention and greater emission of gases. Make sure your products are durable and can resist a range of tough conditions easily.

Review of the Best Duramax Glow Plugs

The market is bombarded with all sorts of products. Cheaper products are marketed in a way to make them seem impressive, but it’s all a hoax. We want you to end up with a durable and reliable model, so we have scoured the internet to find you the best possible brands. Compare them against their pros and cons to access their quality.

Best Overall:
Wellman Fast Start Glow Plugs


  • Come with an excellent warranty
  • Allows for greater thermal conductivity
  • Can control the currents to heat coil faster
  • Durable build makes them last for a longer time
  • Protects your engine against corrosion and misfires


  • Installation is time-consuming

What Recent Buyers Report

The unit peaks at approximately 40A, an upper limit much higher than many other models, making it one of the best models in the market. It also has the perfect lower temperature that stabilizes the engine. All this helps ensure a long-lasting Glow Plug that will need less frequent repairs and replacements.

Why it Stands Out to Us

Wellman is mostly known in the market for its amazing thermal conductivity. With Glow Plugs, this is an essential feature because it ensures that your engine doesn't take much time to heat up. Moreover, good conductivity also improves fuel efficiency and reduces waste. 

The model will also effectively control the current to ensure the rapid heating of the coils. This also has the added advantage of protecting the coils from any exhaust gas damage. All in all, with Wellman, you can rest assured that your vehicle or its engine won’t have to face any corrosion or vibrations in the long run.

Bottom Line

With its exemplary design, it is no wonder that this unit quickly helps the engine reach the most optimum temperatures. The model also controls the current in the coil, thus ensuring lower amounts of vibration. But most importantly, it comes with high durability and strength, features required for longer shelf life.

DieselRx DRX00057-8


  • Can resist both corrosion and vibration
  • Allows for a relatively faster engine startup
  • Durable build provides a much longer shelf life
  • Helps you reach optimum temperatures quickly
  • Comes with added insulation for high heat resistance


  • Labor costs for repairs are high
  • Installation guide is difficult to understand

What Recent Buyers Report

Buyers are content with the working of this model, and why shouldn't they? DieselRx helps protect your vehicle from corrosion and unnecessary vibrations. When riding the vehicle, buyers have noticed that their cars remain stable and steady, even on sloppy roads. Moreover, the higher durability of these plugs has also impressed most buyers.

Why it Stands Out to Us

There are many reasons that this model stands out to us, but to cover all these features is almost impossible, so we will stick to only a few. The superior electrical insulation provides better protection to the exhaust engine, and the double insulation provides greater heat resistance. 

Other ways in which these Glow Plugs help provide safety is by controlling the current that is needed for the coil to heat up. This not only limits the current use but also helps save on fuel consumption. Stability is also another feature that is unique to these units. You will feel your engine heating up to a consistent level each time. This suggests that the plugs do not fluctuate in their function at any time.

Bottom Line

If you want your engine to quickly reach the most optimum temperatures, then this is the product for you. DieselRx is a fine unit that comes with durable construction and a sleek design that is easy to install. But the reason why you need this unit is because of the added insulation it provides. All this helps ensure greater heat resistance that protects your engine.

Best for the Money:
Carb Omar Set of 8 Glow Plugs


  • Provides greater safety features
  • Package comes with installation manual
  • All parts go through multistep quality control
  • Simple yet efficient design makes installation easy
  • Suitable for all models of Chevrolet from 2001-2004


  • Does not come with a good warranty
  • If one plug breaks, the whole set needs to be replaced

What Recent Buyers Report

Users couldn’t be more pleased with the superb performance of Carb Omer. These small units are not very expensive, and a pack of eight can be bought easily. Moreover, all parts of the plugs are tested and have gone through several quality control mechanisms to ensure higher strength. But what buyers love the most is the simple design that makes usage easy and effective.  

Why it Stands Out to Us

You will be amazed to use these amazing units. They are equipped with the latest safety features, such as high insulation that protect your engine. But what sets Carb Omer apart is the high compatibility. You can use these Glow Plugs with several Chevrolet Silverado. 

You will also like the simple yet effective design of the unit that enables its easy installation. In most instances, you won't even need a professional to get it fixed. You can use the manual and follow simple guidelines to help ensure safe and effective installation.

Bottom Line

This 100% patented design has become a household name with more and more people using it for their vehicles. It is an excellent replacement for your old, worn-out plugs. Carb Omer comes in a set of eight plugs that are all made with super-heat technology, thus providing them with greater heat resistance. So if greater safety and protection are at the top of your requirements list, then this is the brand for you.

Best LBZ Duramax Glow Plug:
Allmotorparts Glow Plugs of 1


  • Installation is fairly easy
  • Available at an affordable price 
  • Compatible with most vehicles in the market
  • Can start the engine faster in colder weathers
  • Reduce misfires in the engine to a large degree


  • Does not come in a set
  • If one piece breaks, the whole system needs to be replaced

What Recent Buyers Report

Glow Plugs need to be placed on top of the cylinder heads, and this unique requirement demands greater consideration. Buyers were a bit apprehensive while investing in this model because the design is fairly simplistic. But now that they have used the product, they are wholeheartedly content with both the shape and design.

Why it Stands Out to Us

These very professional units tend to meet and exceed societal expectations. They are made in a way that prevents both corrosion and vibrations in your system. But that's just one of the many reasons for the brand's popularity. You can install them right off from the box, and the whole process hardly takes any time. 

They are also self-regulating, which allows them to control the amount of electrical current that enters your battery. This also helps ensure that the temperature inside the engine doesn't exceed too much. But if overheating does occur by chance, these Glow Plugs come with an effective mechanism to limit the harm to the vehicle.

Bottom Line

Glow plugs have to preheat the air around them in the combustion engine and kickstart the diesel engine in cold weather. This requires a sophisticated design, which is exactly what you get with this model. These plugs tend to be highly compatible with most vehicles. Moreover, they come with a smooth texture and high resistance, thus providing you and your vehicle with greater safety.

Best ACDelco Glow Plug for Duramax:
ACDelco 9G Professional Glow Plug


  • Full range can reach up to 40mm
  • Can avoid overheating at all times
  • Comes with the GN-type regulating coils
  • Has a self-regulating coil that controls electrical airflow
  • Meets chamber requirements in a wide array of applications


  • Pack contains only one Glow Plug
  • Installation requires a professional

What Recent Buyers Report

With so many great products in the market, buyers had to contemplate a great deal before finally buying the ACDelco, and they have not been disappointed. These plugs are very professional and ensure the results of the highest degree. They also come with self-regulating tendencies that put your mind at ease in very cold weather.

Why it Stands Out to Us

When it comes to Glow Plugs, brand reputation is really important. A good brand will be reliable and will also put your mind at ease with warranties and repairs. ACDelco has been in the market for quite some time now and has always managed to impress customers. Even with their Glow Plugs, they have exceeded expectations. 

These units allow for a full range that reaches up to 40 mm. This is enough to meet all the chamber requirements in several applications. Moreover, the lower limit also helps you achieve greater stability. But what sets the model apart is the inclusion of a GN type regulating coil. This allows faster heating of the diesel, thus saving both time and energy. 

Bottom Line

The model is worthy of being on this list for a plethora of reasons. It gives your diesel engine the right amount of heat to kickstart it. With high heat resistance, it also protects you from any possible injury or accidents. So if you want a worthy investment for your Duramax, make sure you consider these plugs first.

Benefits of Investing in Quality Glow Plugs

Replacing your old and low-quality Glow Plugs with new ones can provide several benefits. You can not only get your vehicle running smoothly in no time, but you can also limit the operating costs and utility bills, but more on that later. Here are some of the most notable benefits of making such an investment.

Quick Heat-up Times

One great use of these small units is that they improve combustion inside your cars. This, in turn, leads to a better fuel economy and a much better performance. The engine that holds these plugs usually maintains a perfect temperature range around 200 degrees Fahrenheit. This is the ideal temperature for the smooth vaporization of your fuel.

Better Heat Retention

You need to remember that good heat retention inside the vehicle is a good thing, especially in very cold weather. This also refers to the amount of heat your vehicle will store in a given time. With good quality Glow Plugs, heat retention can remain consistent over time, thus ensuring better and smoother results.

High Heat Resistance

Heat retention and heat resistance are often confused and sometimes used interchangeably. You want high heat resistance in your engine because when you are driving, and your car is overheating, it is possible that the temperatures can cause the antifreeze in your vehicle to boil. This then leads to unnecessary expansion inside the engine, which results in an intense pressure build up inside the radiator hose. A good quality plug prevents this.

Lower Emissions

This is another important benefit as it achieves two very important things; a lower carbon footprint and lower utility bills. A set of durable and long-lasting plugs will ensure greater optimization of energies. This reduces the emission of greenhouse gases and helps you protect your environment.

How to Change Glow Plugs on a 6.6 Duramax

Even if you plan on hiring a professional to change and replace your plugs, you should at least know the basics of the procedure. This is because many emergencies can demand that you do it yourself. And should such a situation prevail, we would want you to rise to the occasion. Here is how you change Glow Plugs.

  1. First, locate the relay power box on your vehicle. This will be a small plastic box that should, in most cases, be located on the right side of your engine compartment. You can also look for it near the wheel well.

  2. Then, open the power box. You can press the tab lightly on the lid and pull it up simultaneously. Make sure you are gentle with this procedure.

  3. Now, examine the interior side of your box. There is going to be a wiring diagram there that shows the proper wiring of the engine. It also shows where the Glow Plugs go.

  4. Next, examine the center carefully and look for your plugs near the engine compartment.

  5. Then you need to place a socket wrench over the entire range holding the units.

  6. The next step is the most crucial one and needs to be done with precision. You need to twist the socket wrench and move it towards your left side. 

  7. Keep doing it till the plug is loose. Never attempt to remove the whole set entirely from the socket. This will damage part of your engine.

  8. Then remove the plugs with your hands and make sure they are all out.

  9. Next, insert the new Glow Plugs in the exact position tightly by using a socket wrench.

  10. If you are replacing more than one Glow Plug, repeat the procedure for each of the units.

If you are still unclear about the steps, make sure you have a quick look at the video below.


When you detect a fault in your Glow Plugs, there is usually very little time to waste, and you need to find a replacement as soon as possible. Looking for such a product on the internet can be hard and can often result in you reaching a faulty decision. But fear not because we have done all the research for you. Simply give this article a quick read and see which model suits your needs the most.

Once you have selected your Glow Plugs, make sure you hire a professional for installation. Or if you intend to save on costs and replace them yourselves, make sure you read the guidelines properly. 

People Also Ask

People usually have a hard time understanding things that require some level of technical skills. But one go at this article is enough to teach you all the prerequisites. If you still have some ambiguities, here are some common FAQs answered.

How Many Glow Plugs Are in a 6.6 Duramax?

In most cases, this number is limited to eight. Since 2006, Duramax diesel engines make use of a complete Glow Plug system that features eight individual units. This is universal for engines all over the world, and in most instances, one faulty plug indicates a fault in all others.

How Much Does it Cost to Replace Glow Plugs on a Duramax? 

Like with most things, the cost of replacing these units also differs. You can find a suitable product for less than $100. However, if you are looking for more durable and reliable brands, then you might want to lose some extra bucks. Labor costs will also have to be paid. These will cost you about $100 to $200 on average.

How Do You Remove a Broken Glow Plug on a Duramax?

It is not safe to drive with a broken Glow Plug inside the diesel engine. And if such a situation arrives, you should instantly remove the unit. The best way to do it is to seek professional help. The labor costs aren't very high, and the precision and accuracy that are needed can only be provided by a trained technician.

How Long Do Duramax Glow Plugs Last?

This also depends on the brand and company that you use. But on average, a good quality unit will last for more than 100,000 miles easily. It can also go on for longer, but it's recommended that you replace the plugs once they have completed their life expectancy period.

Will a Diesel Run Without Glow Plugs?

Contrary to what people think, a lot of big diesel engines don’t have any Glow Plugs in them at all. Smaller diesel engines usually require extra heat and an added push to allow for greater compression. These plugs also help small engines atomize and ignite the fuel faster and without any noise. 

Are Glow Plugs Easy to Replace?

The simple answer to this is yes. Glow Plugs are very small devices, and once they have lost their efficiency, they can be replaced within a few minutes. The removal of old units and the installation of new plugs follow the same procedures. You will have to refer to the guideline mentioned above to know the proper procedure of replacement.

Should I Replace All the Glow Plugs?

Most plugs, especially the ones used in smaller diesel engines, need to be replaced in a complete set of eight. This is essential because having different wear and tear resistance within the same system can cause problems for your car. Moreover, not replacing them altogether will require you to keep a greater check on them. This wastes both your time and energy.

What Are the Symptoms of Glow Plug Failure?

There are some very simple ways to know when your product is failing and can no longer sustain its function. With Glow Plugs, things like engine misfiring, the emergence of white or black smoke, and decreased fuel efficiency are hints enough to indicate that your plugs are failing miserably.

Can Bad Glow Plugs Affect MPG?

If your units malfunction or their function deteriorates in any capacity, they will be unable to provide the additional heat needed for effective diesel combustion. Failure to do this will also lead to engine misfires. This, in turn, leads to a loss of power, decreased fuel efficiency, and decreased acceleration.

How Often Should You Change the Glow Plugs in a Duramax Diesel Engine?

This depends on the brand of Glow Plugs as much as it depends on the climate and temperatures that surround you. These units have a hard time doing their job in extremely cold weather and hence might require frequent replacement. But if you live under normal conditions, you can replace the product once it has reached a limit of 100,000 miles.

How to Test Duramax Glow Plugs

Ideally, this should take a few minutes only, as testing is pretty easy. You can simply connect a 12-volt test light to any positive battery terminal. Then you need to disconnect the wires from each other and touch the probe of the test light to see whether your plugs are working fine.

Sean comes from the forums actually and drives an OBS Ford. He writes fantastic DIYs and knows his way around a camera, too. We keep him caffeinated and away from DPF filters to avoid another rant about recent emissions restrictions.