Re: 2010 vs. 2011 Spark Plugs
They have changed the operation heat range of the spark plugs. Looks to me as if they went up two heat ranges on the plugs. They may have changed nothing as GM has never released to much detail on their heat ranging on plugs.
They have most likely found the engine runs better with hotter plugs.
I will know more when I change mine. But looks like we have another option we can use.
* 1st number denotes THREAD SIZE
* 2nd number denotes HEAT RANGE
In the early 1990s, an all-numeric, identification code was developed to ensure that the proper spark plug would be selected for replacement in specific engine applications. The numeric code does not in any way correspond to the heat range of the spark plug. Therefore, selection of a spark plug with a different code number is not recommended. The heat ranges may be drastically different between two different plugs, and engine damage or poor performance may result. See your local installer or retailer for details.
The prefix “41” stands for the manufacturer’s product line (e.g., 41 = spark plug)
Numbers after the prefix indicate the type of spark plug and also the specific application:
* 100 – 199 = Iridium
* 600 – 699 = Resistor
* 800 – 999 = Double Platinum
2013 Traverse FWD LT1 Black Granite<br /> All-Star Edition.