7A-2 AUTOMATIC TRANSMISSION
I I
M - INDICATES TRANSMISSION
TYPE IN OPTION LIST. (SPECIFIC MODEL CODE IS FOUND ON THE I MX - DESIGNATES
11 SERVICE PARTS IDEMTIFICATIOM I 1 00 MOT REMOVE I
1G3AR47YXE5
C90 C95 DF3 D3C 033 0 GI GW9 G60 GU2 G89
JAl JA4 KO5 K22 Kg9 LV2 NA5 NB1 NKl NK3 N33 N67 GJW
T87 UJ3 U23 U35
VO8 V10 WC3 WG2 YT9 Y56 OIL 6SC 428 421 420
Figure 2 Service Parts ldentificaiton Label
TRANSMISSION DEFINITIONS
The following definitions are being provided to
establish a common language and assist the user in
describing transmission related conditions. Some of
these terms or conditions are used in the transmission
sections of this Service 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 the
accelerator pedal travel.
Wide Open Throttle (WOT) - full travel of
the accelerator pedal.
Full Throttle Detent Downshift - a quick
apply 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 condition where the engine
is used to slow the vehicle by manually
downshifting during a zero throttle coastdown.
Shift Conditions
'a Bump - a sudden and forceful apply of a clutch
or band.
Q 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.
e Delayed - a 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 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 noticeable quick apply of a clutch or
band that is considered
normal with a medium
to heavy throttle shift. Should not be confused
with "HARSH" 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 to "FIRM." This
condition is considered undesireable at any
throttle position.
Hunting - a repeating quick 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 that 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
engagement.
Soft - a slow, almost unnoticeable clutch apply
with very little shift feel.
Surge - a repeating engine related feeling of
acceleration and deceleration that is less intense
than "CHUGGLE.
"
Tie-Up - a condition where two opposing
clutches are attempting to apply at the same time
causing the engine to labor with a noticeable loss
of engine rpm.
,e Conditions
Gear Noise - a whine, most noticeable in first
gear and reverse that is related to vehicle speed.
A gear noise condition may become less
noticeable or go away after an upshift.
Pump Noise - a high pitch whine that increases
in intensity with engine
rpm. This condition may
also be noticeable in
"PARK" and "NEUTRAL"
operating ranges with the vehicle stationary.
