A/T - 700R4 Elimination Of Checkball
SIL 88-36 (Oct)SUBJECT: THM 700-R4
Elimination of the No. 9 Checkball in 1988 Models
The 1-2 shift line-up in the valve body has been changed in the 1988 models to a 2 valve line-up. this eliminates the need to separate lo and detent oil with the # 9 checkball located in the case (See figure 1).
All previous models have at least three valves in the 1-2 shift valve train. Check the 1-2 shift valve train when questioning whether a # 9 checkball should be installed.
The # 5 checkball in the valve body was eliminated in 1987, and is not used in 1988.