Here's more detail about the transmission from jeep.ca
Easy rider. The Compass Continuously Variable Transaxle has no gears, so it doesn't shift conventionally. Instead, it employs a system of two pulleys connected by a strong steel-spined, steel segmented vee belt. The result is a smoother, quieter, more efficient driving experience.
How it works:
Picture a bicycle chain drive, but replace the sprockets – one large and one small – with pulleys and replace the chain with a steel vee belt. The CVT2 operates by varying the working diameters of two pulleys. The pulleys have V-shaped grooves in which the connecting belt rides.
One side of the pulley is fixed; the other side is movable, actuated by hydraulic pressure. When actuated, the hydraulic pressure can increase or reduce the amount of space between the two sides of the pulley. When the width of the groove of one pulley is made wider, the belt rides lower in the groove, effectively reducing the working diameter of that pulley.
In the meantime, the width of the groove in the other pulley is made narrower, causing the belt to ride higher in the groove, effectively increasing the working diameter of that pulley. To suit power
requirements and driving conditions, the system automatically varies the width of the grooves in the two pulleys – one made wider, the other made narrower – continuously varying the “gear” ratio, without the steps normally associated with conventional automatic transmissions.