Impala V6-231 3.8L VIN A 2-bbl (1982)
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Turbine Shaft: Customer Interest
A/T - Burned Clutches/Cracked Turbine Shaft
Number:
84-177
Section:
7A (VIIc)
Date:
July, 1984
Subject:
BURNED OVERRUN CLUTCH, FORWARD
CLUTCH, AND 3-4 CLUTCH PLATE ASSEMBLIES
Model and Year: ALL THM 700-R4 - 1982 THRU
1984
TO:
ALL CHEVROLET DEALERS
Beginning April 16, 1984 (Julian Date 107), a new input housing and shaft assembly and oil pump assembly went into production for
all models of the THM 700-R4 transmission. In addition, new torque converters went into production for all 298 mm applications (4.1L
in-line L6; V8 gas and diesel engines).
FIGURE 1 - Transmission Identification
All transmissions built starting with Julian Date 107 are stamped with the letter "T" on the pan rail after the transmission identification
number (Figure 1). The letter "T" will only be used for the remainder of the 1984 model year.
These production changes eliminate the possibility of burned clutch packs in the input housing due to hairline cracks which could
develop across the ring grooves in the turbine shaft. A crack in this area of the turbine shaft on models built prior to this change could
cause one or any combination of the following clutches to slip and overheat due to loss of apply pressure:
A.
Overrun Clutch Pack
B.
Forward Clutch Pack
C.
3-4 Clutch Pack
SERVICE INFORMATION
1.
If any 1982, 1983 or 1984 THM 700-R4 transmission (built prior to Julian Date 107) experiences burned clutch packs within the
input housing assembly, check for a possible cracked turbine shaft.