This incredible bit of gearing has appeared on HowStuffWorks prior to. Chances are you'll figure out it from the electric screwdriver article. An automatic transmission includes two full planetary gearsets folded jointly into just one part. See How Equipment Ratios Get the job done for an introduction to planetary gearsets. https://cristianoybaa.bloggosite.com/41067848/rumored-buzz-on-gearbox-auto