John Deere 6030-series tractors: John Deere announced in September 2006 that it was replacing its 6020 Premium tractor series with the 6030 Premium line. The lower spec 6020 SE continued to fly the 20-series flag until these, too, were replaced by 6030 ‘standard’ models a year later. Now that all 6030 tractors are starting to appear on the used market, James de Havilland suggests some pointers for potential buyers