I have a 2005 Dodge Ram 1500 and work at a sawmill where the sawdust flows EVERYWHERE (talk about the WORST place to work with a black truck!). Anyway, the dust gets into the fresh air intake on the cowl and then blows into the cabin thru the vents.

I know they make ventilation filters for semi-tractors. I am curious if anyone knows of such a filter for a Dodge Pickup? If so, where can I find it? I have just about Googled my brains out trying to find one!

Not sure about your truck but on cars with them a lot of times they are around or in the windshield wiper cowl.
But before you look to much drop by you dealer and ask him if it has one and the try to find out where.
MT