(8-Pack) NGK Spark Plugs IZTR5B11 (Stock # 1465)

Perform flawlessly in my 2011 silverado. Pre-gapped. No real gas mileage increase. Motor runs better now though ! Always easy to install and they usually last !

These are the correct spark plugs for GM 4.8 thru 6.0 liter engines, they were also set to the revised factory spec of .40 of an inch. They were packaged well and shipped with collars around the threads, to not only protect the threads, but also the electrode from being bent if package is dropped. If these maintain their price of roughly $64 for 8, then this is a great deal. My truck's 4.8 runs smoothly and power is very good, I would dare say feels like a brand-new truck. So far these have worked well, I am also using the Edelbrock 22716 Ultra Spark 50 spark plug wires, will come back and edit review if the spark plugs fail for some reason. Currently I highly recommend these spark plugs.

No issues to install works really good. Install on my 05 avalanche

I always use NGK Sparkplug for all of my vehicle. Last a long time, smooth idle, and peace of mind. You can never go wrong with NGK. These fit and help smooth out the idle of my 2010 chevy 1500, mpg improved a little bit.

Right on time and excellent service

Had a misfire in cylinder 5, after installing these the check engine light went away in ≈10 miles. Came in different sized boxes which I found wired but they all appeared to be the same.

The media could not be loaded. Good spark plugs for good price, seems to work very well. I plan to change my plugs at 50K miles. They came gapped at 0.040”, some places says they’re gapped to 0.044, the OE gap for my vehicle is 0.040I used the Laser iridium as they’re good for 80K miles, the iridium IX is good for up to 50K miles.Recommendations:I added a small amount nickel anti-seize to the threads due to the carbon buildup on the old plugs.Dielectric Silicone paste on the boots goes a long way, I used Mission Automotive silicone paste.Overall I would buy again.

Spark plug gaps were perfect out of box. There is a noticeable difference. Truck runs a lot better I run ethanol the plugs were nasty and corroded. Keep an eye on that for those who run ethanol I bought plugs and wires for a 2011 Chevy Tahoe fit like a glove