[xsalvationx]

For my XB would putting a 2 12in sub box in the back lower the MPG? I figure since the box is kind of on the heavy side. hno:

 

[sovereign]

not unless the sub box was a few hundred pounds lol

 

[Chrevis]

i have 2 15's and i haven't noticed a drop in gas, if there is any, it's not much.