Air filter box

[riverhawk]

What year did gm start using the one big hole air inlet vs the two small hole inlets on earlier years?

[davedyno]

What year did gm start using the one big hole air inlet vs the two small hole inlets on earlier years?

I don't know what year about the two small holes, but I do know the one inlet hole in fender on my 2011 Silverado is a lot larger then my 2002 Silverado fender air inlet hole. Also GM changed the part number for the replacement ACDelco paper airlifter. Filter does not look as restrictive as the one the came on truck, mybe a tiny bit better airflow.

Dave

[WilliamBos]

Does the HD air filter still exist? Thats all I ran in my 04, worked great st keeping finbe dust out.