Originally Posted By: oilstudent24
I also was wondering if there is much difference between The OEM Ford Paper vs Wix paper vs Purolator classic Air filter in regards to pleats/airflow/airbox seal.
Unfortunately there is, at least with my application (2002 Ranger).
For some reason, Purolator left out the lower "step" in the gasket that you will find on an OEM filter and most aftermarket filters. This part of the gasket is essential to sealing the air box properly. Without it, the two halves can move around, potentially allowing dirt to get by. Most Purolator products are fine, but I just can't use their air filters in my truck knowing the air box isn't sealed properly. If the gasket for you application looks just like OEM, I would expect it to be fine.
I've actually found that Fram air filters seal the air box the best in my truck. They have nice thick gaskets. I won't use their oil filters, but I will gladly buy their air filters.