8 New NGK Iridium IX Spark Plugs TR6IX # 3689

Replaced original motorcraft platinum plugs with these NGK iridium today. Old plugs didn't look too bad but there is a noticeable difference in acceleration and it idles smoother. Love my car a lot so I try to treat her well. 👍🏻👍🏻

I have not yet noticed any mileage improvement as I had not driven much of the vehicle that was installed these plugs yet. It was just for a peace of mind that I knew that the plugs were all brand-new. I did not realize that the vehicle had Bosch iridium plugs already in it...but a mechanic (or sales person at the shop) told me that I was right to go with NGK...whatever that means. I did tell them to pre-gap does not match the vehicle (2011 CVPI) spec. so adjustment was needed. Not even sure they did or not but Engine fired up no problem and seems like running better!? I am going to fill it up and see what king of MPG I get with these plugs soon.

My tuner said to go with these plugs upon a tune up. Glad I did! Granted the previous owner didn't take care of the truck to my standards, so I went through with a deep tune up. The truck idles much smoother now and with these plugs, the tuner was able to bump spark advance up.The truck went from not even thinking about spinning the tires on dry pavement to burning them off! Granted I know this directly isn't plug related, but even before the tune, these made the truck idle MUCH smoother and start faster.

I have an LSA boosted 5.3 in my 2005 Tahoe, which is prone to spark knocking when the engine is loaded in a higher gear; even with 93 octane gas and octane booster. These plugs helped eliminate the ping to the point the knock sensors don't detect it. 3000 miles and no fouling at this time.

Great customer service if needed. These work well in my 07 tahoe with a lsa blower. Much better then the tr6 I pulled from it that gave a rough idle. These are new technology so use it and stay away from the old style plugs if want better response and idle quality when boosted. On 12 lbs 14 degrees timing no kr.

Works just as advertised, car started right up.

Pre gapping

For the price cheaper than every where else. worked great for my ls4 impala ss. pain to do the tune up but worth it!