What qualifications have you got? cipralex uk GM also promises better fuel economy, although exact fuel economy estimates are not yet available. The SUVs will be available with an improved 5.3-liter V8 engine which will include high-tech features like cylinder deactivation in which half the engine’s cylinders are shut off when full power isn’t needed. The engine will also have direct fuel injection and continuously variable valve timing. The SUVs will also be equipped with a new six-speed transmission.