Can you replace 255 r70 16 tires with 215 r60 16 tires?

Absoulty not if the 255/70-16 is the OEM tire size. The 215 will be 13% smaller in overall diameter. You should never, ever go over 3% different. You would have to go to a 275/60-16 to even be close to 3% and then it would be 3.5% smaller.