Bonneville V6-231 3.8L (1984)
Throttle Valve Assembly: All Technical Service Bulletins
A/T - Harsh 1-2 and/or 3-4 Shifts
Number
84-7-43
Date
11/84
Subject:
HARSH 1-2 AND/OR 3-4 SHIFTS - ALL 1984 MODEL THM 200-4R TRANSMISSIONS
Some 1984 THM 200-4R transmissions may exhibit a harsh 1-2 and/or 3-4 shift. This harsh 1-2 and/or 3-4 shift may be caused by a damaged or
mispositioned T..V. Boost valve spring.
Starting April, 1984, a new control valve assembly which has a new T.V. Boost valve spring went into production on all 1984 model THM 200-4R
transmissions to correct his harsh 1-2 and/or 3-4 shift. (Refer to Chart 1 for part numbers and model applications, and Chart 2 for Julian date breakpoints
when the new control valve assembly went into production.)
On transmissions built before the Julian dates in Chart 2, if a condition of harsh 1-2 and/or 3-4 shift is experienced and the cause is the damaged or
mispositioned T.V. Boost valve spring, use the new control valve assembly.
FIGURE 1
The Julian date is shown on the nameplate (Figure 1). The nameplate is attached to the right rear side of the transmission case.
CHART 1
NEW CONTROL VALVE ASSEMBLY
MODEL AND PART NUMBER APPLICATIONS
MODELS
CONTROL VALVE ASSEMBLY
PART NUMBERS
AA, AP
8639343
BQ
8639914
BT, BY
8639912
CH
8639393
CQ
8639400
CR
8639414
HE
8639424
HG
8639431
OF, OY
8639326
OG
8639452
OI
8639462
OM
8639915
OZ
8639343
CHART 2
JULIAN DATE BREAKPOINTS WHEN NEW CONTROL VALVE ASSEMBLY WENT INTO PRODUCTION
MODELS
JULIAN DATE
AA
116
BQ
109
BT
115
