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Dealer Technical Bulletins - Section 12 - Chassis Electrical, Instruments
Content last modified: June 13, 2026 at 10:06 am
Bulletin 68-I-24 — Pontiac Motor Division Dealer Service Information Bulletin, Section 7F (Two-Speed Automatic Transmission). Attention: Service Manager.
Subject: Two-Speed Automatic Transmission — Component Identification.
Short answer: This bulletin provides a comprehensive component identification table for the Two-Speed Automatic Transmission used in 1966–1968 Pontiac and Tempest models, listing the vacuum modulator, governor, valve body, spacer plate, converter assembly, and downshift timing valve part numbers along with their transmission model usage and identification markings.
| Component | Year | Engine | Trans. Model Usage | Service Part No. | Identification |
|---|---|---|---|---|---|
| Vacuum Modulator | 1967–68 | 6-cylinder with A/C | LD, LH | 1365187 | Brown paint daub on cover |
| 1967–68 | 6-cylinder exc. A/C | LA, LB, LF, LG | 1367032 | White paint daub on cover | |
| 1967–68 | V-8 with A/C | MC | 1377046 | Green paint daub on cover | |
| 1967–68 | V-8 except A/C | MA, MB | 8623947 | Service part no. or production part number 8623365 stamped on cover | |
| Governor | 1966–68 | 6-cyl. and V-8, 4-Bbl. | LA, LB, LD, LF, LG, LH, MB | 1377893 | “X” stamped on governor thrust cap |
| 1967–68 | V-8, 2-Bbl. & with A/C | MA, MC | 1374587 | Plain thrust cap on governor | |
| Valve Body | 1967 | 6-cylinder, 4-Bbl. | LB, LG | 1378251 ¹ | Yellow paint daub on production valve body solenoid |
| 1967–68 | 6-cylinder, 1-Bbl. | LA, LF | 1378257 ¹ | Pink paint daub on production valve body solenoid | |
| 1967–68 | 6-cylinder with A/C | LD, LH | 1378257 ¹ | Brown paint daub on production valve body solenoid | |
| 1968 | 6-cylinder, 4-Bbl. | LB, LG | 1378257 ¹ | Blue paint daub on production valve body solenoid | |
| 1967–68 | V-8, 2-Bbl. & with A/C | MA, MC | 1378257 ¹ | Green paint daub on production valve body solenoid | |
| 1967–68 | V-8, 4-Bbl. | MB | 1378257 ¹ | Black paint daub on production valve body solenoid | |
| Spacer Plate | 1967 — All 6-cyl. engines | All 6-cyl. | LA, LB, LD, LF, LG, LH | 1381098 | VVV notches cut in outer edge of spacer plate |
| 1967 — All V-8 engines | All V-8 | MA, MB, MC | 1386305 | ||
| 1968 — All 6-cyl. engines | All 6-cyl. | LA, LB, LD, LF, LG, LH | 1378517 | ||
| 1968 — All V-8 engines | All V-8 | MA, MB, MC | 1384917 | ||
| Converter Assembly | 1967 — All 6-cyl. engines | All 6-cyl. | LA, LB, LD, LF, LG, LH | 9776990 | Brown paint daub on cover |
| 1968 — All 6-cyl. engines | All 6-cyl. | LA, LB, LD, LF, LG, LH | 9792251 | Violet paint daub on cover | |
| 1967–68 — V-8, 2-Bbl. & with A/C | V-8 | MA, MC | 9776991 | Brown paint daub on cover | |
| 1967–68 — V-8, 4-Bbl. | V-8 | MB | 9776991 ² | Black paint daub on cover | |
| Downshift Timing Valve | 1967 | 6-Cylinder, 4-Bbl. | LB, LG | 3829920 | Orange stain on outer end of valve |
| 1967 | V-8, 4-Bbl. & with A/C | MB, MC | 3829920 | Orange stain on outer end of valve | |
| 1968 | V-8, 4-Bbl. & with A/C | MB, MC | 1366164 | Red stain on outer end of valve |
1 Service part number 1378257 is common to all 1967–68 transmission service usage.
2 For service replacement, use 9776991 converter, identified by a Violet paint daub.
Content last modified: June 13, 2026 at 10:06 am
Content last modified: June 13, 2026 at 10:06 am
Content last modified: June 13, 2026 at 10:06 am
Content last modified: June 13, 2026 at 10:06 am
Content last modified: June 9, 2026 at 7:10 am

