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In order to illustrate the constant development of the automatic transmission controls area, this paper describes how the garage shift calibration works in vehicles with transverse front wheel drive powertrains. A garage shift (GS) is the turbine speed transient commanded by the shift lever movement from Park to Drive or Reverse, from Neutral to Drive or Reverse, from Drive to Reverse, from Reverse to Drive, or from Drive or Reverse to Neutral [1]. A usual metric to verify the garage shift comfort is the data acquisition of the fore-aft acceleration on the seat track, but also the shift time should be considered, as well as the clutch energy and the repeatability of the shift feeling for different temperatures and engine idle speed levels. This paper demonstrates the transmission calibration strategies to determine a sensitive and a non-sensitive garage shift and its interactions with the engine calibration.

This work is dedicated to study of time reduction for automatic transmission validation on emissions cycle. It has also summarized the main emissions regulations with their emissions cycles tests, like the US FTP-75 and European NEDC. Data acquisition was conducted through emissions cycles tests in a chassis dynamometer in four vehicles. Graphics were generated using the data collected showing driving time in each gear, the total amount of upshifts and downshifts, elapsed time in engine speed range and elapsed time in accelerator pedal range. Result showed that was not possible to eliminate validation tests completely, but it can be minimized and contributes to reduce timing in automatic transmission validation work due to running fewer tests.