spark plug help

[uchi]

hey guys, i bought some plugs for my 09 sierra with the 5.3 a short while back and im finally getting around to putting them in. theyre a delco plug part number 12621258 41-110

 

the kid at the parts store said thats what my truck took, i puled a plug from my truck and its different, its a 12609877 41-985

they appear to be identical in length from where it seats in the head its just shorter where the plug wire connects to it. i did some googleing and it says the plug i bought it for an older gm vehicle and not for my 09. will these still work since theyre the same length or should i return them just to be on the safe side? i know gm offers a platiunum and iridium plug for my truck, if i remember correctly you need iridium if planning on running e85, which im not so either plug should work for me.

[uchi]

im still searching this out, these guys are referencing both part numbers i mentioned

 

http://www.gmtruckclub.com/forum/showthread.php/25446-AC-Delco-Spark-plugs-Iridium#axzz1s1tTwEIA

 

saying gm replaced the plug, so im assuming these will work then

[uchi]

put them in, seems to run and theres no piston to spark plug love sounds being made, lol

[txab]

41-110 replaces 41-985. Both are iridium. You're fine

[uchi]

thats what i had figured too but i just wanted to be clear, thanks

[txab]

thats what i had figured too but i just wanted to be clear, thanks