This past Monday the Mustang and automotive enthusiast world was shocked by news out of Steeda that the 2015 Mustang would weigh in 200-300 pounds more than the outgoing 2014 model. This seemed contrary to what we’d previously been told by Ford, that the 2015 would utilize weight saving materials.

Much like the 2015 F-150, which sheds hundreds of pounds through the extensive use of aluminum throughout the truck, including its body, the 2015 Mustang will do the same. No word yet on exactly what panels on the body, if not all will be made from lightweight aluminum, however we know that several suspension components will be constructed from aluminum based on information released from Ford.

Steeda is now offering an explanation as to how they arrived at the estimated weight gains. In a statement on the Mustang6g forums, user Seth@Steeda says “Based on our experience working with IRS mustangs in the past we estimated what the weight addition will be. In addition current industry trends with new cars show additional weight being added for various new safety and comfort features. “

While we agree that IRS in the past has added more weight, and that new comfort features also generally add a few pounds, we have to wonder if Steeda got it wrong, as Ford is seeming to learn from past mistakes with the 99-04 Cobra IRS system, developing a car specifically for such a system this time around. We had assumed that Steeda’s blog post was based in fact from information derived in the CAD data released through the SEMA Tech Transfer program on June 1 by Ford for the 2015 Mustang. That doesn’t seem to be the case here.

It just goes to show that until the official numbers are released by Ford, and members of the press (us included) have the opportunity to get into the car and thrash it properly, no one outside the Ford engineers really know what this car will be like.