X4XZ Double Iridium Spark Plugs 41-109 6-Pack for GM 3.0L/3.6L V6 — OE Fit, Longer Life

X4XZ 41-109 double iridium spark plug set (6 pieces) is a direct-fit ignition upgrade engineered to restore reliable starts, smoother idling, and consistent combustion for compatible GM V6 engines.

This six-pack of OE-replacement spark plugs is built around a double iridium electrode design to deliver longer life and stable firing across a wide range of General Motors vehicles. Each plug follows OE dimensions and fitment to make swap-outs straightforward for DIY mechanics and technicians. The set replaces common OE numbers (including 41-109 / 41109 and several cross-references) and is optimized for drivability, cold starts, and steady acceleration without complex tuning.

Which vehicles and engines are these spark plugs compatible with?

These X4XZ plugs are targeted at many GM models equipped with 3.0L and 3.6L V6 engines from the 2010–2018 model years. They cover Cadillac, Chevrolet, GMC, Buick, and select Saturn models; always verify your engine code and OE part number before purchasing.

• Cadillac: ATS, CTS, SRX, STS, XTS 3.0L/3.6L applications (2010–2018)
• Chevrolet: Camaro, Caprice, Colorado, Equinox, Impala, Malibu, Traverse 3.0L/3.6L
• GMC: Acadia, Canyon, Terrain 3.0L/3.6L
• Others: Saturn Outlook/Vue V6 and Buick Enclave/LaCrosse V6

How does double iridium improve ignition and longevity?

Iridium is a high-melting-point metal used on both the center and ground electrodes to reduce wear and maintain a sharp firing edge far longer than conventional copper or nickel plugs. That sharper electrode produces a concentrated spark that ignites air-fuel mixtures more reliably, which helps with consistent starts and smoother throttle response over the plug's service life.

• Double iridium center and ground electrodes resist erosion for extended service intervals
• Cleaner, more focused spark improves combustibility and reduces misfires
• Manufactured to meet or exceed OE fit and reach for reliable installation

Will installing these plugs affect fuel economy or emissions?

While no component alone guarantees a specific MPG gain, restored ignition consistency often leads to improved combustion efficiency and fewer incomplete burns. Replacing worn plugs with X4XZ double iridium plugs typically results in smoother running and can marginally improve fuel usage and reduce unburned hydrocarbons compared with badly worn electrodes.

• More complete combustion can reduce wasted fuel during acceleration
• Stable spark timing minimizes misfires that harm emissions performance
• Longer-lasting electrodes mean consistent performance between service intervals

What should I expect during installation and maintenance?

These plugs are built to OE specifications so installation mirrors standard spark plug replacement procedures: remove old plugs, check gap if necessary, torque new plugs to manufacturer spec, and reinstall any ignition coils or connectors. The set ships as six plugs and does not include printed instructions, but most owners or technicians can complete the job with common hand tools.

• Replace in sets as recommended by vehicle manufacturer for balanced ignition
• Check torque and use anti-seize only if specified by installer guidance
• Regular inspections recommended; iridium life expectancy is substantially longer than standard plugs

Who is this for: The X4XZ 41-109 double iridium 6-pack is aimed at DIYers, independent shops, and fleet managers seeking a durable, OE-fit replacement for GM 3.0L and 3.6L V6 engines. Choose this set if your vehicle shows rough idle, reduced throttle response, or if you’re performing scheduled tune-up maintenance and want a longer-lived ignition component without modifying ignition timing or engine controls.