Detent Switch (Thm 400); Vacuum Modulator (Thm 400) - GMC G Service Manual

7A-68 TRANSMISSION

DETENT SWITCH (THM 400)

H
Remove or Disconnect (Figure 74)
1. Wire connector.
2. Screw.
3. Switch (260).
Install or Connect (Figure 74)
1. Switch (260).
2. Screw.
3. Wire connector.
l^ \
Adjust (Figure 74)
1. Press the plunger (A) as far forward as possible.
2. Press the accelerator pedal to the floor.

VACUUM MODULATOR (THM 400)

H Remove or Disconnect (Figure 75)
• Raise the vehicle.
1. Vacuum hose.
2. Screw (271).
3. Retainer (270).
4. Vacuum modulator (178).
5. Vacuum modulator valve (15).
6. Seal (269).
Clean
• All parts using soapy water. Air dry.
Inspect
• Modulator and pipe for kinks, cracks and damage.
• Vacuum hoses for cracks, wear and dry rot.
K H Install or Connect (Figure 75)
1. Vacuum modulator (178).
• New seal (269).
• Vacuum modulator valve (15).
2. Retainer (270).
3. Screw (271).
4. Vacuum hose.
] Important
• The pipe must not be twisted or bent.
Figure 73 — Transmission Filter and Pan
Figure 74 — Detent Switch (THM 400)