Spark Plugs for 5.3 Silverado – Buyer’s Guide!

Written by Lucas Kaderly

The Chevrolet Silverado is a full-size heavy-duty pickup truck manufactured by General Motors. The first model was introduced in 1998 as the replacement for the Chevrolet C/K line.

The 5.3 Silverado uses a Vortec 5300 (5.3 L) V8 engine that comes with a 4-speed automatic transmission.

List of Top-Rated Spark Plugs for 5.3 Silverado

ACDelco 41-103 ACDelco 41-103610.4 ouncesView on Amazon
NGK 90813 TR5AI-13 NGK 90813 TR5AI-1340.8 ouncesView on Amazon
ACDelco 41-110 OEM Gm 12621258 ACDelco 41-110 OEM Gm 12621258812.8 ouncesView on Amazon
Bosch 9602 Bosch 960211.6 ouncesView on Amazon
NGK TR5IX 7397 NGK TR5IX 739780.10lbsView on Amazon

You might think that a spark plug is a simple part of your engine’s performance, but in fact, it’s a precision tool that must withstand constant high electricity arc (lightning bolt) within a combustion chamber. So, it has to both produce voltages from 20K-100K and also withstand extreme explosions and heat constantly.

Spark plugs are connected to the ignition coil via the distributor cap. The center electrode and the ground electrode react creating a spark of energy in the gap. This gap spark or bolt of electricity is the spark required to ignite the fuel-air combination in the engine combustion chamber.

The spark will only fire when the voltage increases over 20KV, then the spark plug is “breached,” and the spark is delivered.

The Best Spark Plugs for 5.3 Silverado Reviews

ACDelco 41-103 – Professional Iridium Spark Plug (6 Pack)

ACDelco 41-103


The ACDelco 41-103 Professional Iridium Spark Plug comes as a pack of 6 for all 5.3 Silverado applications.


The central electrode material is nickel and has an iridium tip. The hex size is 16mm, and the insulator material is made from a high Alumina ceramic. This is a ribless design, and the seat is tapered. The shell coating is zinc plate, and the design comes with a fixed terminal top.


  • Iridium tipped electrode for 4,000-degree Celsius performance
  • One-piece suppressor seal


This is a budget-friendly model and comes from a brand name, so you are not getting a cheap part, you are getting a quality component from a good brand name at a very attractive price.

NGK 90813 TR5AI-13 – Laser Iridium Spark Plug, Pack of 4

NGK 90813 TR5AI-13


This is the NGK 90813 TR5AI-13 Laser Iridium Spark Plug that comes in a pack of 4


This model uses a fine wire nickel central electrode with an iridium tip. The ground electrode has a platinum tip for improved performance.

This is a classic 14mm thread with a tapered seat and a 5K Ohm resistor. The terminal is a solid type with a 0.50” gap. The shell is made from cast iron, and the insulator is made from Alumina Silicate Ceramic.


  • Trivalent Metal Plating
  • Corrugated Ribs Prevent Flashover
  • Alumina Silicate Ceramic Insulator
  • Copper Core for Heat Removal
  • Triple Seals Prevent Leakage


This is a high-grade spark plug that uses a platinum tip ground electrode, this raises the price of the product but also increases performance.

ACDelco 41-110 OEM Gm 12621258 – Professional Iridium Spark Plug – Set of 8

ACDelco 41-110 OEM Gm 12621258


This is the ACDelco 41-110 OEM Gm 12621258 Professional Iridium Spark Plug that comes in a set of 8.


When it comes to top-level performance that comes with a top-level price, then you will want this iridium tipped spark plug model that comes as a set of 8.

This model uses a one-piece suppressor seal for effectively blocking out RF interference.

This model comes with a standard nickel electrode with an iridium tip.


This is a great brand, but if you like paying more for less, then go for it. Adelco is great, but paying top dollar for a name that delivers the same performance as any other top brand name is a bit tough for me.

Bosch 9602 – Double Iridium Spark Plug, Up to 4X Longer Life (Pack of 1)

Bosch 9602


This is the Bosch 9602 Double Iridium Spark Plug, comes in single units.


Now we are talking top-tier manufacturing, its hard to beat a Bosch, and this is the Bosch Double Iridium Spark Plug.

This model comes with an ultra-fine wire design, and laser welded tapered ground electrode.

The center and ground electrodes are both iridium, hence the “double” iridium name.

This has a gap size of 1, with a 16mm hex and the shell is nickel-plated steel for improved protection and thermal resistance. There is a copper core for improved heat transfer.


  • Double Iridium electrodes
  • OE Replacement
  • OE-matched spark position for compatibility with new Gasoline Direct Injection (GDI) technology
  • 4X Longer Service Life: compared to standard copper spark plugs


It is a perfect package of modern technological ingenuity, and nothing beats this model, the price is steep but less than the ACDelco, which makes this a downright winner for any driver that seeks a stress-free performance from their engine.

NGK TR5IX 7397 – Iridium IX Spark Plugs (pack of 8)

NGK TR5IX 7397


This is the NGK Iridium IX Spark Plugs TR5IX # 7397 that comes in a pack of 8.


This model uses fine wire nickel with the iridium tipped central electrode. It has a 14mm thread and an 18mm reach. The terminal is a solid type with a 5K Ohm resistor, and the model is a taper cut with a standard shape.

There is a trivalent metal plated shell with an Alumina Silicate Ceramic Insulator and a copper core for added thermal transfer.


  • Fine Wire Nickel Center Electrode
  • Iridium Alloy tip
  • Trivalent Metal Plating
  • Corrugated Ribs Prevent Flashover
  • Alumina Silicate Ceramic Insulator
  • Copper Core for improved Heat transfer
  • Triple Seals Prevent Leakage


This is an efficient spark plug model, comes with the standard features for an OEM performance and the price is adequately marked.

5.3 Silverado Spark Plugs FAQ

Spark Plug Construct

A spark plug might look simple, but every component is matched for its materials integrity for insulation, thermal resistance, electrical conductivity and ability to withstand vibration and extreme condition changes.

Let’s take a look at the components in a spark plug:

Insulator: The insulator body is high-pressure dry molded from an aluminum oxide ceramic. This molding is kiln-fired, and the end product is an insulating body that has exceptional dielectric strength, high thermal conductivity, and excellent shock resistance.

Ribs: These are part of the insulator body and are used to improve the grip of the rubber spark plug boot against the plug body. Some models do not have ribs.

Shell: The shell comes under the hex and is usually made of steel or steel billet (bar stock).

Hex: This is the part of the shell that lets the socket wrench install or uninstall the unit.

Plating: To assure durability and resistance to corrosion, the steel shell is always coated with a protective layer.

Gasket: Some spark plugs use gaskets, some are “gasketless.”

Threads: All plugs come with threads, these are SAE standardized sizes for each application.

Ground electrode: The ground electrode is made from a nickel alloy steel for extreme resistance to corrosion and thermal extremes.

Center electrode: Center electrodes are also made of a thermal and corrosion-resistant material. These tend to vary between manufacturers.

Spark park electrode gap: This is the gap between the two electrodes and is where the spark will occur.

Insulator nose: This is the insulator body part that is seen at the electrode gap area, it must be resistant to carbon, oil, and fuel deposits at low speeds, shedding them to retain a clean gap area.

As you can see, a spark plug has to be a precision machined component that delivers constant energy to the engine, as such, keeping your spark plugs clean and maintaining them is a must-do maintenance activity every year.

How to change spark plugs

Maintaining the integrity of your engine includes maintaining a good set of spark plugs. Spark plugs wear over time, and some wear faster than others. This occurs even when installing a full set of plugs from the same kit.

Spark plugs essentially wear over time as the heat burns the electrode contact points. When an electrode is fully worn down it will not spark properly or at all. This then leads to engine misfires, and you will hear and feel the difference in engine performance.

Other issues related to spark plugs are cracked insulator bodies that will need to be fully replaced too. There is spark plug refurbishes that specializes in taking old spark plugs and remanufacturing them, so when you change your plugs, don’t throw them away, sell them to a refurbished.

COP Plugs

For the more mature driver or mechanic that changed plugs before 2000, or for car owners that have both pre-2000 and post 200 vehicles, the new coil-on-plug (COP) ignition systems might seem confusing but are easier to work with when replacing spark plugs. While they don’t use distributor caps, the process for changing a plug is virtually the same.

Changing a Plug

Before you go and change a plug consider cleaning the old ones first and drawing out every bit of life from them. If you don’t want any issues and are willing to install a new set, then go ahead, that’s not a real big issue when it comes to motor maintenance. To be honest, its always better to change a full set of plugs and not just one at a time.

When you unscrew a plug, take a look at it, in most cases, you will see the electrodes are worn down a bit, don’t get in fluster, this is their natural state after use. What you don’t want are blackened tips with a lot of soot or grim. This means you have engine issues.

Don’t Wait till it’s Too Late

I don’t condone waiting the maximum time to replace plugs, these parts are not expensive like brake pads, and are key to your overall daily performance. As such, replacing plugs based on performance requirements is key. This means, don’t wait for 100,000 miles, or even 80,000 miles, check them every 10,000 miles. Unscrew your plugs to assure they don’t seize, which they do overtime. Check them, clean them, and reinstall them. This will prolong their life, but will also show you which plugs require replacement.

Replacing Steps

Start by cleaning your work area; this means using compressed air to blast around the engine and the ignition coils; this will prevent dirt from falling into the cylinders.

The next step is to remove the plastic covers, if there are any, and remove the air cleaner assembly from the engine top. Always label your hoses and wires before removing them.

After removing these parts, give the engine a blow of air again.

For now COP engines, just pull the boots off the plugs.

For COP, the next step is removing the ignition coil; this usually takes a quarter turn to loosen the O-ring seal and lift the part out. Now depress (or pull up) the locking tabs of the ignition coils electrical connector and remove it. Slowly take the connector off the coil. Now undo the coil hold-down bolt and pull the coil and boot assembly out completely.

Now you need to blow again, make sure the entire surface area is spic and span.

Take a spark plug socket wrench and unscrew the plug. Once again, use air to clean the dirt and grunge that’s accumulated around the plugs bed.

Now you can install the new plugs, or after you clean the old ones, return them.

When you install a plug, make sure you have a gap gauge, they are not expensive, and are a mandatory item for proper precision installation.

Never install a plug without checking the gap!

About the author

Lucas Kaderly

Lucas Kaderly is a 34-year-old divorced driving malcontent. Bitter that he’s stuck driving a RAM 1500 instead of a two-door sports coupe, he loves his truck as much as he loves to rail at the injustice of modern society and lash out at the city’s incompetent drivers. In his short (close to 17 years) driving experience he’s had a good fortune, and in some cases, bad luck, to drive some automobiles.


  • Nice article. Thank you for suggesting all types of Spark Plug. I want to change my car spark plug. I have decided that replace with Bosch 9602 Double Iridium Spark Plug. I like it’s a great feature.

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