Just want to know what this pakage consists of

 

3.55 rear gears instead of the now standard 3.31 gears.

 

Ford realized that many customers buying 2013 Mustang GT's with the manual transmission want 3.55 or 3.73 gears while the cars on the lot with 3.31's were sitting around unsold. So, to help move them, Ford reinvoiced the unsold '13 GT's with 3.31's with the axle promo to discount the cost of those cars to help sell them. It's kinda like a rebate, but is right on the window sticker as a factory equipment discount.