I've had the K&N air filter (in the stock airbox) on my truck for 2-1/2 years now. I just received my first oil analysis: "Universal averages show typical wear metals for an oil from this type engine after a routine run on the oil. ... all wear read below average. "
I think the biggest problem with the K&N (or any filter) is making sure there is a good seal between the filter and the airbox.
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1996 Dodge 2500 4X4 SC, SLT, Cummins 12V, 5-spd. , JRE 4" exhaust (my kitty ran off into the woods and the muffler fell off!), TST 280 HP/685 Ft-Lb Uprate Kit, AFC Spring Kit, Horton Fan Clutch, Jacobs/Ram Exhaust Brake, MagHytec Differential Cover, Prime-Loc, Rancho RS9000 Shocks, Combo Gauge, K&N Filter, Brite-Box, Geno's finger-touch oil pan drain plug, no turbo silencer ring, full-time fog lights.
I think the biggest problem with the K&N (or any filter) is making sure there is a good seal between the filter and the airbox.
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1996 Dodge 2500 4X4 SC, SLT, Cummins 12V, 5-spd. , JRE 4" exhaust (my kitty ran off into the woods and the muffler fell off!), TST 280 HP/685 Ft-Lb Uprate Kit, AFC Spring Kit, Horton Fan Clutch, Jacobs/Ram Exhaust Brake, MagHytec Differential Cover, Prime-Loc, Rancho RS9000 Shocks, Combo Gauge, K&N Filter, Brite-Box, Geno's finger-touch oil pan drain plug, no turbo silencer ring, full-time fog lights.