Boom Extension/RetractionDANGERBefore operating the boom, make sure thatnobody is within the working range of themachine.To extend or retract the telescopic elements of theboom:Smoothly shift the lever to position D toextend the boom or to position C to retract it.Controls And InstrumentsOperator’s ManualPart No. 57.0009.0540GTH-4013 SX - GTH-4017 SX - GTH-4013 EX - GTH-4017 EX57First Edition - Second PrintingCourtesy of Crane.Market