In the transition from lockout hubs and cast-iron gear-driven T-cases someone figured this little piece of awesomeness for the Dana 30: the central axle disconnect. It wasn’t needed as evidenced by millions of TJs and XJs running around without it. Get rid of it. The cheap way is to use an XJ or TJ long-side shaft, a piece of steel, and a regular Dana 30 inner axle seal. You gotta pull the carrier, but every CAD housing we’ve seen was already machined for that inner seal. Or the 4x4 Posi Lock is under $160 and includes a new aluminum housing, cable, hardware, and instructions to manually control your front axle engagement from the cab.