What is the biggest 15 inch tire you can put on the back of a 1962 impala?

The biggest 15-inch tire you can typically fit on the back of a 1962 Impala is around 255/70R15 without significant modifications. However, some enthusiasts have successfully installed larger tires, such as 275/60R15 or even 295/50R15, depending on the specific wheel offset and suspension setup. It's essential to ensure there’s enough clearance in the wheel wells to avoid rubbing, especially during turns or when the suspension compresses. Always consider consulting with a tire or automotive specialist for the best fitment based on your vehicle's modifications.