1988 Chevrolet Pick-up Truck Differential Spool K1500 - GM 8.5 in. - w/ 10 Bolt Cover - 28 Spline - Spartan Locker - Installs into standard open carrier case - Front guaranteed to replace your current 1988 Chevrolet Pick-up Truck Differential Spool K1500 - GM 8.5 in. - w/ 10 Bolt Cover - 28 Spline - Spartan Locker - Installs into standard open carrier case - Front. 1988 Chevrolet Pick-up Truck Differential Spool comes new OEM 1988 Chevrolet Pick-up Truck Differential Spool aftermarket new 1988 Chevrolet Pick-up Truck Differential Spool of remanufactured 1988 Chevrolet Pick-up Truck Differential Spool K1500 - GM 8.5 in. - w/ 10 Bolt Cover - 28 Spline - Spartan Locker - Installs into standard open carrier case - Front.