Shift Conditions

Bump - a sudden and forceful apply 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 - condition where a shift is expected but does not occur for a period of time. Samples of this condition could be described as clutch or band engagement that does not occur as quickly as expected during a part throttle or wide open throttle apply of the accelerator or, when manually downshifting to a lower range. Also defined as LATE or, EXTENDED.

Double Bump (Double Feel) - two sudden and forceful applies of a 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 a shift as compared to the feel at the start of the shift. Also defined as END FEEL or, SLIP BUMP.

Firm - a noticeably quick apply of a clutch or band that is considered normal with a medium to heavy throttle. Should not be confused with MARSH or ROUGH.

Flare - a quick increase in engine rpm accompanied with a momentary loss of torque. This most generally occurs during a shift. Also defined as SLIPPING.

Harsh (ROUGH) - a more noticeable apply of a clutch or band as compared with FIRM. This condition is considered undesirable at any throttle position.

Hunting - a repeating series of upshifts and downshifts that causes a noticeable change in engine rpm. An example could be described as a 4-3-4 shift pattern. Also defined as BUSYNESS.

Initial Feel - a distinct 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 repeating jerking sensation similar to CHUGGLE but more severe and rapid in nature. This condition may be most noticeable during certain ranges of vehicle speed. May also be used to define the condition after converter clutch engagement.

Slipping - a noticeable increase in engine rpm without a vehicle speed increase. A slip usually occurs during or after initial clutch or band apply.

Soft - a slow, almost unnoticeable clutch or band apply with very little shift feel.

Surge - a repeating engine related condition of acceleration and deceleration that is less intense than CHUGGLE.

Tie-Up - a condition where two opposing clutches and/or bands are attempting to apply at the same time causing the engine to labor with a noticeable loss of engine rpm.