Do you put chains on 2 or 4 tires?
Driving with Tire Chains
Four-wheel drive vehicles should use tire chains on all four tires. You must use tire chains for those wheels on the drive axle for two-wheel drive vehicles, but it's much safer and easier to control if you have chains on all four tires. via
Do you need chains on all 4 tires with AWD?
A: Yes. All vehicles must carry tire chains or cables when entering chain-control zones, although you may not need to put them on your tires, depending on the weather. Under restriction levels R1 and R2, chains do not need to be installed on four-wheel-drives or all-wheel-drives that have snow tires on all four wheels. via