I recently purchased a 2000 Sport 4 door with the 5.9l in it...the motor has a GForce chip and an aftermarket air filter, dunno the name brand, looks like a kn but it fits into the stock housing...anyways... truck is getting around 11 miles to the gallon, was reading and thought I might need to change the MAP sensor for a little better milage...is there anything else besides maintainance I may need to try? This is a 4x2 btw, will post pics af her later. Thanks!