4 New NGK IRIDIUM IX Spark Plug LTR6IX-11 # 6509

Worked great on my 2013 mustang boss

Replaced the 19 year-old spark plugs in my Mazda MX-5. Experienced an intermittent check engine light and occasional acceleration hiccup, after install installation of these and new coils no more check engine light and smooth acceleration, even when the engine is cold.

Bought these to get iridium plugs back in my truck the factory changed to Platinum spec plugs for service intervals and they have a much shorter service life. Did them at 85K miles because I drive pretty hard and I found the factory recommended changing plugs at 65K if you tow a lot. I figured heavy right foot probably simulates some towing and the gap was out of spec already. Anyways, truck runs awesome, definitely idles and accelerates a smoother in traffic. Installed at the factory set .043” from NGK. Lots of people online freak out about it not being a .055” gap for the coyote. They run great. If anything they will burn to a .055” gap after a couple years of driving. But with these efficiently and performance results, I am very happy with these plugs in my 2018 F150 5.0 V8 Coyote

These were perfect for my 2016 F-150. Gapped easily and fit great. Would highly recommend these NGK plugs.

Just as I expected

All but one were close to the recommended gap, the one off was .20 off but with the tool you can open the gap or close for what’s recommended for your engine. This fits good for a 2013 F150 5.0, works great.

Excellent spark plugs that were properly pre-gapped for our Mazda Miata. Nice to have that "spark" back in the engine. LOL!

Just what I needed for my 2026 F-150 5.0L V8. These are not cheap but should last another 100,000 miles.