C 2500 3/4 Ton Pickup 2WD V8-350 5.7L VIN M 4-bbl (1984)
FIGURE 2 - 4-3 DOWNSHIFT SWITCH WIRING DIAGRAM PRIOR TO JULIAN DATE 065, 1984
Models built prior to Julian Date 065 were built with a solenoid and "O" ring assembly that has a 4 wire harness which uses the 4-3 downshift switch
(Figure 2).
FIGURE 1 - 4-3 DOWNSHIFT SWITCH WIRING DIAGRAM BEGINNING JULIAN DATE 065, 1984
The 4 wire harness is superseded by the 3 wire harness (P/N 8654129). When servicing the 4 wire harness, replace it with the 3 wire harness and bypass
the 4-3 downshift switch as shown in Figure 1.
