After a break from side loader design Wynyard’s penchant for innovation led to the release of the SL4020, the first 40’/20’ container side loader in Australasia and legal on New Zealand roads for 40’ containers. With a lift capacity up to 35 Tonne the notable features were the Swinglift™ side loader’s new Leg-Over stabilisers and hydraulic slide cylinders fitted for changing the crane lift module position on the chassis for 20’ or 40’ container cartage capability. This new Swinglift design which also complied with NZ road regulations effectively superseded the standard trombone side loader models that were at that time being produced by competitors, and which were proving very restrictive in 20’ and 40’ container cartage.

While the first SL4020 model was built with a typical I-Beam chassis, it soon became apparent that tare weight and low maintenance slide systems were important factors for transport companies. The Lattice chassis was introduced which proved to be very robust and providing a low tare while retaining strength for heavy containers. The lift modules were mounted on chromed round bars that that formed the top chord of the chassis ensuring smooth transitions and accurate module placement. It has been proven that the slide bushes in the crane modules can last up to 15 years or more saving time and maintenance costs when compared against other designs.