Why not a 2 speed or quick change rear end option

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I'd be satisfied with the ability to force an earlier shift, and lock-up, on the 4R100 auto on our 2000 F-250 7.3L. As it is, it does not shift to OD, nor converter lock-up, until about 40 mph even when there is virtually no load. If I had a manual, I'd be short-shifting around town while running empty.

Wes
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