I read through the supplemental owners manual yesterday after picking up my new truck and they say to stay away for aftermarket performance filters, but after reviewing the K&N website their drop in filter for the 6.7L is heavy duty with 6 layers of material vs. the standard 4 layers.

Does anyone have experience with K&N E-0787 drop in air filter? Good or Bad? Safe to use on truck. Looks at $60 or so to pay for itself after a few changes considering the standard air filter is about $20.

 

Ive ran K&N on my gassers but i would be warry about putting one on my cummins. That turbo moves a lot more air and under load it can suck the oil out of the filter. I did an oil change on a 5.9 that had a K&N and i pulled the tube off the turbo, the blades were nothing but black and greasy, can only imagine what the intercooler looked like.

 

don't run an oiled filter on any turbo diesel engine. Diesel turbo's draw a lot more air in than even a gasoline turbo does. Like was said, it will suck the oil into your turbo and make a mess, then the filter without the oil will be less effective at filtering.

if you want to run an aftermarket, get an oil-less filter. AFE makes k&n style filters without the oil, and better filtration capabilities. I run an AFE filter with my compound twin turbos that draw in massive amounts of air to produce 65psi of boost in the manifold... if you pull the tubes off my turbos and look at the compressor wheels, they are spotless.

 

I noticed they make two styles in the dry flow, the flat panel & a deep sitting cone style that is drop in the stock air box. Which style is better? Flows more air?

 

The deep cone type should have more surface area resulting in better airflow. It probably cost more to.