Rock Tamers Mudflap System 00108 2" Hub with Matte Black Stainless Steel Trim Plates

how much does this effect your fuld mileage ?

I have a 2 1/2" ball mount, how much room is needed on the top and sides?

can anyone tell me the ideal size gap to have between the road and bottom of the mud flap? Mine are dragging & I’m not sure how much to take off?

can I get a 2 1/2 center hub only. I have both a 2” and 2 1/2” application. Will a 2 1/2” center hub work ok on a 2” application. Thanks?