Marc Urbano|Car and Driver The Lexus IS has compact dimensions and either rear- or all-wheel drive. Marc Urbano|Car and Driver The IS350 is the sole model in the lineup and is powered by a naturally aspirated 3.5-liter V-6 engine. Marc Urbano|Car and Driver The rear-drive IS350 pairs that engine with an eight-speed automatic, while the all-wheel-drive version, which we tested, gets a six-speed gearbox.