Best Spark Plugs for 5.3 Silverado

Best Spark Plug for 5.3 Silverado

In order to keep your 5.3 Silverado engine running at its peak performance, you need to replace the spark plugs as part of your regular maintenance plan. Spark plugs are extremely durable and will withstand millions upon millions of explosions before finally wearing out. The best spark plugs are high-quality OEM plugs. So, what are the important factors that make these OEM spark plugs the best fit for your Silverado pickup truck? Let’s take a look at 6 of the best spark plugs and determine which may be the best for your driving situation.

Best Spark Plug for 5.3 Silverado – Top Picks:

AD Spark Plug Pack Find on Amazon88862397 748UU 748HH 748GG 19297035, WGM48 9748UU 9748HH 9748GG 88862397 88862385
NGK #1465 Find on Amazon‎1465
41-962 Spark Plugs Find on Amazon41-962 19299585, 748HH 748GG 19297035, 88862397 88862385 748UU, WGM48 9748UU 9748HH 9748GG
AC Delco 41-962 Find on AmazonACEEK00038
Bosch (9602) HR8LII33UFind on Amazon‎9602
HiVehicle Iridium Find on Amazon‎EBUS003

The condition of your spark plugs is directly tied to your engines performance. As the spark plugs age they can affect the engine’s ability to start when the engine is cold, horsepower output, and fuel efficiency. Worn out plugs can eventually cause the engine to begin misfiring and increase the temperature of exhaust gases, which may cause damage to the catalytic converter. Many vehicle owners think that all spark plugs are the same, which is not true. Only their primary function is the same.

Preliminary Heat Range

The operating temperature of a spark plug is the most important factor. Controlling this temperature is critical. A “hot” spark plug will transfer heat slower and be more apt to foul. What can be confusing is that the higher the performance level of the engine, the colder a spark plug needs to be.

Best Spark Plug for Preliminary Heat Range: AC Delco 41-962

Shell Design

Some cylinder heads may accept different shell designs. If the correct shell design is not selected, you could end up with inconsistent heat range and potential engine damage. Shell design includes spark plug thread diameter, thread length, or reach, and type of seat design necessary for your engine’s cylinder heads.

Best Spark Plug for Shell Design: NGK #1465 Laser Iridium IZTR5B11 Spark Plug Pack

Electrode and Gap Style

Spark plug nose configuration comes down to one simple rule: the more the spark plug is exposed to the fuel/air mixture, the easier it is to initiate combustion. There are two basic types: conventional (regular) or projected styles. The projected style projects the spark further into the combustion chamber and usually results in better performance. If high performance is your goal, use the projected style, unless there isn’t enough clearance for the projected style.

Best Spark Plug for Electrode and Gap Style: Bosch (9602) HR8LII33U Fine Wire Iridium Spark Plug Pack

AC Delco 41-962 Spark Plug Pack

AD Spark Plug Pack

To start with, the 41-962’s are easy to install even if you are new to automotive maintenance and may be doing this for the first time. This is the original plug installed at the factory so there is no doubt that it will work well. The center and ground electrode have a double platinum point pad that will deliver constant voltage, better fuel mileage, and excellent performance. These spark plugs come with a 7-year warranty from AC Delco. The only downside to double platinum is that it is the poorest performer when compared to copper or iridium tipped spark plugs.

This plug package includes new spark plug wires. It is important when replacing spark plugs to also replace the wires. The wires are responsible for carrying the voltage to the combustion chamber. If your plug wires are degraded, those new plugs will not be able to deliver the performance you need.


  • Includes new wires and heat shields
  • OEM recommended replacement parts
  • Durable, efficient, and affordable


  • Plugs need to be gap checked before installing
  • No sleeve to protect the bridge on the plug
  • Less conductive than copper

NGK # 1465 Laser Iridium IZTR5B11 Spark Plug Pack

NGK #1465

These spark plugs are often specified as a replacement for original equipment. They are guaranteed to meet or exceed OE quality and performance. Because they are precision laser welded, the iridium tip is six times harder than platinum, which provides superior ignition performance.

They have a platinum pad on the ground electrode for even wear. They also have an alumina silicate insulator that adds physical strength and will help transfer heat away from the tip, which will help eliminate misfiring. Combustion gases will not leak through the shell due to the triple gasket sealing of these spark plugs.


  • Laser welded iridium centers
  • Will last from 80K to 100K miles
  • Triple-gasket sealed shell
  • Superior anti-corrosion and anti-seizing properties
  • Iridium tip six (6) times harder than platinum


  • Higher priced than copper or platinum spark plugs
  • Virtually no fuel mileage increase noted by purchasers
  • Performance improvement may not justify the added expense

AC Delco 41-962 Spark Plugs & 9748HH Herlux Spark Plug Wires

41-962 Spark Plugs

This spark plug is high on performance and resists corrosion. They are a direct replacement of the spark plugs that were originally installed on you vehicle at the factory. With a double platinum point pad on the center and ground electrode, you will get the performance that you expect.

The Herlux plug wires have thick silicone jackets that will reduce heat and abrasion resistance as they carry the spark to the combustion chamber. Herlux wires are able to withstand the harsh conditions that exist inside the engine compartment.


  • Direct factory replacement spark plugs
  • Easy to install
  • Double platinum point pads


  • Wires are long and may need to be gathered and tied
  • Platinum not as conductive as copper or iridium

AC Delco 41-962 Platinum Ignition Spark Plug Set

AC Delco 41-962

If you are looking for durable, efficient, and affordable, the AC Delco 41-962 double-platinum spark plugs should be considered. They will deliver high-quality performance for your Silverado at a more than reasonable cost. They are GM original equipment and that makes them simple to install. With double platinum on both the ground and the center point pads, voltage delivery to the combustion chamber will be consistent.


  • Improved gas mileage
  • Easy to install – original GM design
  • Both center and ground electrodes have a double platinum point pad.
  • 7-year warranty


  • Platinum not as conductive as copper or iridium

Bosch (9602) HR8LII33U Fine Wire Iridium Spark Plug Pack

Bosch (9602) HR8LII33U

These Bosch spark plugs have a double iridium firing pin and ground electrode inlay that will provide 4 times the service life when compared to copper spark plugs. You can expect these spark plugs to last for 100,000 miles. In fact, they come with a 7-year performance guarantee. They work extremely well and will improve your vehicle’s ignition response, fuel mileage, and performance.

The fine wire design requires up to 24% less voltage to ignite. Their copper core provides a wider heat range to resist fouling. They come pre-gapped for quicker installation. That said, many purchasers complain that they can be somewhat more difficult to install.


  • Very durable
  • Improve fuel mileage
  • Corrosion resistant
  • Require up to 24% less voltage to ignite
  • 7-year performance guarantee


  • Can be difficult to install
  • Iridium spark plugs are on the more expensive side

HiVehicle Iridium Spark Plug Pack

HiVehicle Iridium

The HiVehicle Iridium spark plug is professional grade and well suited for the extended range of the 5.3 Silverado pickup. It has a 0.6mm laser welded iridium tip that will provide consistent spark and high stability. It has anti-corrosion and anti- seizing features that will help eliminate combustion gas leakage, improving fuel efficiency. Its updated design will reduce the chance of breaking off during installation and operation.


  • Professional grade
  • Updated design reduces breaking off
  • Anti-corrosion and anti-seizing technology
  • 6mm laser welded iridium tip


  • Complaints about a loss of fuel mileage
  • Misconceptions about part number matching AC Delco OEM plugs


Your Silverado 5.3 may be strictly stock or be built for racing, but it is usually somewhere in the middle of these to extremes. Basically spark plug selection comes down to  shell design, electrode style, heat range and performance. Double platinum spark plugs, preferred for DIS engines or systems without a distributor, provide quick starts, good acceleration, and better fuel economy, with improved durability. Iridium spark plugs are among the most advanced technologically on the market today. They deliver better ignitability, optimum performance, outstanding acceleration, high fuel efficiency, and maximum durability.