2017 Toyota Tundra Spark Plug Type & Gap Specs

As an ASE-certified master technician, I’ve seen my fair share of misfiring trucks rolling into the bay. If you own a 2017 Toyota Tundra, you already know you are driving one of the most reliable full-size trucks on the road. Whether you have the 4.6L V8 or the legendary 5.7L V8, Toyota engineered these powertrains to last. However, maintaining that reliability means staying on top of routine maintenance, including replacing your spark plugs at the correct mileage with the exact OEM-specified parts.

Below is the definitive guide to spark plug types, gap specifications, torque values, and replacement tips for your 2017 Toyota Tundra.

Quick reference: 2017 Toyota Tundra Spark Plug Specs

Note: Motorcraft and ACDelco are not recommended for this Toyota application. Stick to Denso or NGK Iridium plugs.

Why the right plug matters

Modern Toyota V8 engines are highly sensitive to spark plug heat ranges and electrode materials. The heat range dictates how fast the spark plug pulls heat away from its tip and transfers it into the cylinder head. If you use a plug that runs too hot, you risk pre-ignition and engine knock. Too cold, and the plug will foul with carbon.

Furthermore, the 2017 Tundra requires Iridium spark plugs. Iridium is significantly harder and more durable than platinum or traditional copper. The ultra-fine iridium center electrode provides a more concentrated, consistent spark, which is crucial for maximizing fuel economy and ensuring a complete burn in the combustion chamber. Because of iridium's durability, these plugs boast an impressive 120,000-mile replacement interval. Downgrading to copper or platinum will result in a severely shortened lifespan and potential misfire codes.

How to gap a spark plug

The OEM Denso and NGK iridium plugs for your Tundra come pre-gapped at 0.043 inches (1.1 mm) from the factory. However, it is standard technician protocol to verify the gap before installation in case a plug was dropped during shipping.

When checking the gap on an iridium plug, never use a standard coin-style gapper to pry on the center electrode. The fine iridium tip is brittle and will snap off easily. Instead, use a wire-style gauge or feeler gauge to gently measure the distance. If adjustment is absolutely necessary, use a specialized gap tool to bend the ground strap only, applying a light bend without making contact with the fragile iridium center electrode.

Replacement procedure tips

Replacing plugs on the 1UR-FE and 3UR-FE engines is a straightforward job, though it requires some patience due to the bulk of the V8 engine tucked near the firewall.

• Coil-on-Plug (COP) System: The Tundra utilizes individual ignition coils for each cylinder. You will need a 10mm socket to remove the coil hold-down bolts. Gently twist the coil boots as you pull up to break the seal without tearing the rubber.
• The Anti-Seize Debate: Do not use anti-seize on the spark plug threads. Modern NGK and Denso plugs feature a specialized trivalent zinc coating on the threads that acts as a release agent. Adding wet anti-seize alters the thread friction, which can easily lead to over-torquing and damaging the aluminum threads in your cylinder head. Install them dry to 15 lb-ft.
• Dielectric Grease: Apply a small dab of dielectric grease to the inside of the coil boot before reinstalling it over the new spark plug. This prevents moisture intrusion, stops voltage leaks, and ensures the boot won't stick to the plug ceramic during the next service interval.
• Keep it clean: The Tundra's spark plug tubes sit deep in the valve covers. Before removing the old spark plugs, blow compressed air down into the tubes to remove sand, dirt, and debris so it doesn't fall directly into your engine cylinders.

Known issues

Unlike the notorious Ford 5.4L 3-valve engines that suffer from two-piece spark plugs breaking in the head, or certain GM engines with sensitive ionization-sensing coil problems, the Toyota UR-series V8 is incredibly robust. There are no systemic design flaws regarding spark plug blowouts or broken plug shells on the 2017 Tundra.

The most common "issue" technicians encounter on these trucks is simply neglected maintenance. Because the engine runs so smoothly, many owners push the original plugs far past the 120,000-mile mark. This causes the gap to erode and widen, which forces the ignition coils to work harder, eventually leading to premature coil failure. Stick to the interval to protect your ignition coils.

Need plugs replaced? Find a shop on Repairius.