1971 E-Body:
the "014" axle is a 741 case 7260 pinion w/3.23 ratio OPEN & 10" brakes
the "015" axle is a 741 case 7260 pinion w/3.23 ratio OPEN & 11" brakes

the "016" axle is a 489 case 7290 pinion w/3.23 ratio OPEN & 10" brakes
the "017" axle is a 489 case 7290 pinion w/3.23 ratio Sure-Grip & 10" brakes
the "018" axle is a 489 case 7290 pinion w/3.23 ratio OPEN & 11" brakes
the "019" axle is a 489 case 7290 pinion w/3.23 ratio Sure-Grip & 11" brakes