Welcome to ZRoadster.org - BMW Z1 Z4 Z8 Z3 Forum and Technical Database

If you want to join in with the discussion, and see the areas which are available only to members then sign up now!

  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

How automatic gearboxes work

Discussion in 'Performance' started by GazHyde, Jun 23, 2014.

  1. GazHyde

    GazHyde The Gaz Monkey
    Staff Member Administrator Global Moderator British Zeds

    Dec 2, 2011
    Likes Received:
    Trophy Points:
    Newbury, Berkshire
    Model of Z:
    BMW Z4 3.0Si Sport
    Just found a couple of interesting videos about gearboxes and torque converters. I'm not sure how relevant they are to BMW gearboxes, perhaps someone can comment who knows what they are on about!

    The first video explains the principals of automatic transmissions that use a Ravingneaux planetary gear set (means absolutely nothing to me!)

    View: http://youtu.be/Y1zbE21Pzl0

    The second video explains the theories behind a torque converter...

    View: http://youtu.be/z5G2zQ_3xTc
  2. Cooper

    Cooper Zorg Guru (IV)
    Supporter Australian Zeds

    Apr 17, 2014
    Likes Received:
    Trophy Points:
    Hobart Tasmania Australia
    Model of Z:
    3.0i 2001
    @GazHyde I have an automatic step-tronic and love it. It seems really strong and when I place Brandy in park she 'sits down'. Nice beemer, sit, good beemer! 'Quote from Jim Carey in Fun with Dick and Jane. Anyway, when going down a hill at speed the gearbox will grab the engine and use it to slow you down if you tough the brakes, which I hate, so I flick it over into step-tronic and up the gears manually one or two, relieving the backwards pressure and keeping the speed up! Thought I would throw that in there for other members that may not have used that approach. Cooper