Ford's Mustang was redesigned for 2005, getting more power, new features, and styling inspired by its 1960s ancestors. Coupe and convertible models were offered. They gained some 6 inches in wheelbase and overall length vs. the 1999-2004 generation. Weights rose about 100 lb on coupes and 275 lb on convertibles. A new underbody structure replaced one that dated from 1979, but the'05 Mustang retained a solid rear axle rather than adopting independent rear suspension. Both body styles came in base V6 and GT V8 versions, and in Deluxe and Premium trim. The V6 was a 210-hp 4.0-liter in place of the previous 193-hp 3.8. GTs reprised a 4.6-liter V8, but with 300 hp vs. 260. A 5-speed manual remained the standard transmission. The optional automatic had five speeds vs. the previous four. All '05 Mustangs had 4-wheel disc brakes. ABS and traction control were standard on GTs and optional on base models. No antiskid system was available. Base versions had 16-inch wheels and GTs had 17s. Among options new to Mustang were front side airbags that covered torso and head, and an Interior Upgrade Package that included instrument lighting with 125 color choices. All Mustangs came with air conditioning and a CD player. Coupes had 50/50 split folding rear seatbacks. Convertibles included a power fabric top with heated glass rear window. Leather upholstery was standard on GT Premiums and available for other models. GTs included grille-mounted fog lamps and a rear spoiler.