With either the convertible or the sedan, there are two engines to choose from: a 2.5-liter V6 or a 3.5-liter V6. The 2.5-liter engine can be paired with either a 6-speed manual or paddle-shifting electronically controlled transmission. The sedan also comes in a high-performance IS F trim, featuring a 5.0-liter V8 engine and an 8-speed sport direct-shift auto transmission with paddle shifters and manual mode. All versions come standard as rear-wheel drive, though the base sedan is available with full time all-wheel drive optional. The IS and IS C come equipped with VDIM, which manages the electric power steering, stability control, ABS, brake assist, electronic brake force distribution and engine torque systems to detect and prevent skids. Airbags and TPMS are standard on all models, and safety technology options include a pre-collision system that uses sensors to mitigate frontal collisions, a backup camera and adaptive front lighting. The convertible has available sensors that prevent the roof from operating when there are obstacles in the way. Speaking of tech, the IS has tilt-down mirrors to assist with parallel parking, but if that's not enough, the available Intuitive Parking Assist will help by indicating distance from surrounding objects with beeps and on the LCD display. Optional dynamic radar cruise control locks the IS onto the rear bumper of the car in front of it and follows at a constant distance. And in the IS C, a roof brake engages just before the retractable hard top folds itself away into the trunk to minimize mechanical sounds and ease the top into its place. Inside, the seats, steering wheel, and shift knob are trimmed in leather with bird's-eye maple trim. The leather seats in the IS F are bolstered to keep passengers firmly in place while snaking along curvy roads at speed. In place of the wood, the F uses a composite aluminum trim. The Lexus designers took great pains to keep the interior as quiet as possible -- the sedan even includes a sound-absorbing sun visor. Floor braces were added to reduce vibration, and acoustic glass was used in the windshield. The Mark Levinson sound system in the convertible (an option in the sedan and F) automatically adjusts the volume and equalizer to compensate for an open top.