Shift blocking
Automotive transmission feature
Shift blocking is a feature of automobile manual transmissions added to improve fuel economy ratings in the Corporate Average Fuel Economy (CAFE) system by preventing a driver from switching from first gear to second or third as would be done normally. A solenoid prevents the shifter from engaging these gears, forcing the driver to shift from first to fourth gear. The solenoid is computer controlled, and will deactivate if the throttle is opened wide enough, or the car reaches speeds above those typical in city driving.
“Shift blocking” enters the record as automotive transmission feature. Crown Archives preserves that source wording while asking what Shift, blocking and Automotive can confirm, complicate or overturn.
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“Shift blocking” is worth following because a concise public description often conceals a longer documentary argument. Here, Shift, blocking and Automotive provides the most credible route into that argument.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Dec 27, 2025.
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This entry incorporates text from “Shift blocking” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.