A/T - No Upshift Condition After Downshift
Bulletin: 86-7200-2ADate: July, '86
Ref. No.: 86-077A-7200
SUBJECT: NO UPSHIFT CONDITION AFTER DOWNSHIFT
MODELS AFFECTED: 1984-1986 THM 200C, 200-4R TRANSMISSIONS
NOTE: This bulletin supersedes bulletin 86-7200-2 dated, March, 1986.
A 1984 through 1986 THM 200C or 200-4R transmission may exhibit a no upshift condition after a part or full throttle downshift.
This condition may be caused by internal leakage hydraulically locking the throttle valve plunger. If this occurs, the line pressure remains at a boosted level, resulting in a no upshift condition.
FIGURE 1 - THM 200C TRANSMISSION NAMEPLATE:
FIGURE 2 -THM 200-4R TRANSMISSION NAMEPLATE:
FIGURE 3 - TYPICAL 200C CONTROL VALVE ASSEMBLY:
FIGURE 4 - TYPICAL 200-4R CONTROL VALVE ASSEMBLY:
To repair this condition, a new throttle valve plunger and throttle valve bushing, and for some models, a throttle valve lever and bracket assembly should be installed. Refer to Figures 1 and 2 for transmission nameplate identification information and to Figure 3 and 4 for service parts identification. The chart provided indicates service package part numbers, and transmission model applications and 1986 model start of production Julian dates for the THM 200C and 200-4R transmissions .
IMPORTANT: The highlighted transmission models and service package part numbers identify those packages which include the throttle lever and bracket assembly. These service packages were not included in the original bulletin.
* The Highlighted Service packages contain:
(1) Throttle valve plunger
(1) Throttle valve plunger bushing, and
(1) Throttle lever and bracket assembly.
All other service packages contain:
(1) Throttle valve plunger, and
(1) Throttle valve plunger bushing.
(NOTE: Throttle lever and bracket assembly part number 8648670).
** 1986 Model Julian date begins in calendar year 1985.