The base curb weight of the '13 GT auto coupe is 3700 lbs approximately. But my door jam reports 4600 lbs. Here's what Ford says the estimated base curb weight of each model is: Coupe: V6 manual: 3501 lbs V6 auto: 3523 lbs GT manual: 3618 lbs GT auto: 3675 lbs Boss 302: 3631 lbs Boss 302 Laguna Seca: 3636 lbs Shelby GT500: 3845 lbs Convertible: V6 manual: 3600 lbs V6 auto: 3652 lbs GT manual: 3735 lbs GT auto: 3792 lbs Shelby GT500: 3982 lbs I have a GT auto coupe, which is alarming when I see the door jam weight and compare the above numbers: My GT is a Premium with Brembos, and it now has the 3dCarbon front spoiler, GT500 rear spoiler, CS side scoops, and Roush 20-inch rims, so the weight isn't all that accurate, but it must be a good gauge relatively speaking. Do all the extras really amass to 1000 lbs of additional weight? Or is the base curb weight a measurement of something else entirely? What do your door jams report and how does it compare to the base curb weight reported by Ford?