The following definitions are being provided to establish a common language and assist the technician in describing automatic transaxle related conditions. Some of these terms or conditions are used throughout the transaxle sections of this manual.

Throttle Positions

Minimum Throttle: The least amount of throttle opening required for an upshift.

Light Throttle: Approximately 1/4 of accelerator pedal travel.

Medium Throttle: Approximately 1/2 of accelerator pedal travel.

Heavy Throttle: Approximately 3/4 of accelerator pedal travel.

Wide Open Throttle (WOT): Full travel of the accelerator pedal.

Full Throttle Detent Downshift: A quick application of the accelerator pedal to its full travel, forcing a downshift.

Zero Throttle Coastdown: A full release of the accelerator pedal while the vehicle is in motion and in drive range.

Engine Braking: A procedure where the engine is used to slow the vehicle by manually downshifting during a zero throttle coastdown.

Shift Conditions

Bump: A sudden and forceful application of a clutch or band.

Chuggle: A bucking or jerking condition that may be engine related. May be most noticeable when the converter clutch is engaged. Similar to the feel of towing a trailer.

Delayed: A condition where a shift is expected but does not occur for a period of time. Also defined as Late or Extended.

Double Bump (Double Feel): Two sudden applications of the clutch or band.

Early: A condition where the shift occurs before the vehicle has reached a proper speed and tends to labor the engine after the upshift.

End Bump: A firmer feel at the end of the shift as compared to the feel at the start of the shift.

Firm: A noticeably quick application of a clutch or band that is considered normal with a medium to heavy throttle shift.

Flare: A quick raise in engine RPM accompanied by a momentary loss of torque. This most generally occurs during a shift and should not be confused with Harsh. Also defined as Slipping.

Harsh (Rough): A more noticeable application of a clutch or band as compared to Firm. This condition is considered undesirable at any throttle position.

Hunting: A repeating quick series of upshift and downshifts that causes a noticeable change in engine RPM. An example could be described as 3-2-3 shift pattern. Also defined as Busyness.

Initial Feel: A distinctly firmer feel at the start of a shift as compared to the finish of the shift.

Late: A shift that occurs when the engine is at a higher than normal RPM for a given amount of throttle.

Shudder: A repeated jerking sensation similar to Chuggle but more severe and rapid in nature. This condition may be most noticeable during certain ranges of vehicle speed. It may also be used to define the condition after converter clutch engagement.

Slipping: A noticeable increase in engine RPM without a speed increase in the vehicle. A slip usually occurs during or after initial clutch or band engagement.

Soft: A slow, almost unnoticeable clutch application with very little shift feel.

Surge: A repeated engine related feeling of acceleration and deceleration that is less intense than Chuggle.

Tie-up: A condition where two clutches are attempting to engage at the same time causing the engine to labor with a noticeable loss of engine RPM.

Noise Conditions

Drive Link Noise: A whine or growl that increases and then fades with vehicle speed and is most noticeable under light throttle acceleration. It may also be noticeable in the PARK or NEUTRAL operating ranges with the vehicle stationary.

Final Drive Noise: A hum that is related to vehicle speed and is most noticed under light throttle acceleration.

Gear Noise: A whine most noticeable in first gear, second gear, and reverse, and is related to vehicle speed. A gear noise condition may become noticeable or go away after an upshift.

Pump Noise: A high pitched whine that increases in intensity with engine RPM. This condition may also be noticeable in PARK or NEUTRAL operating ranges with the vehicle stationary. The noise may appear louder in DRIVE or in REVERSE.