
Originally Posted by
Brian Hjelm
I think the earthmoving & mining industries have well and truly proven the performance and reliability of torque convertor & auto, semi-auto, & powershift transmissions. No manual trans. whatsoever in any new plant that I know of, and have not been seen for many, many, years. Terex have a 240 ton rear dump with mechanical ( as opposed to electric) drive and auto. trans.
No question whatsoever about this - but very few if any are fully automatic, although torque converters and powershifts are everywhere. And fleet owners everywhere have long since decided that automatics are cheaper to run in cars - but I'm not sure that cheaper = better.
Two interesting points - I was in the USA recently, and did a bit of city bus travel - while most of these are automatic or powershift, I did see a couple of manuals, rather surprisingly in that country. Also of interest is the new (last month) Ford Freestyle my sister-in-law has just got in Houston. It has a continuously variable belt drive transmission, with a multiplate friction clutch. Both are controlled by the ECM and the driver has no control over gearing except for forward and reverse and indirectly by rate of change of throttle opening and the throttle opening itself.
John
John
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
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