The MG3 Getrag is a 5 speed manual transmission assembly.
Important: Use only manual transmission lubricant GM P/N 88861800 (Canadian P/N 88861801) for this manual transmission assembly. Other lubricants or additives may affect the shift performance.
The MG3 Getrag manual transmission has the following features:
| • | First and second gear double coned synchronizer |
| • | Third, fourth, and fifth gear single coned synchronizer |
| • | Three shaft design consisting of an input shaft, output shaft, and intermediate shaft |
| • | Reverse inhibit feature |
| • | One piece clutch actuator - no bleed screw |
| • | Transmission venting system is part of the fill cap |
| • | First gear ratio is 3.58 |
| • | Second gear ratio is 2.02 |
| • | Third gear ratio is 1.35 |
| • | Fourth gear ratio is 0.98 |
| • | Fifth gear ratio is 0.69 |
| • | Reverse gear ratio is 3.31 |
| • | Final drive ratio is 3.94 |
| • | Vehicle speed sensor (VSS) |
The manual transmission shift cables must be adjusted for proper shifter performance.
Lubrication Flow
A common sump supplies oil for the manual transaxle. When the manual transaxle is operating normally, the differential assembly splashes oil from the sump, to provide lubrication. The splashed oil is collected in an oil trough. The oil travels down
the trough at the case end and lubricates the input and output shafts. The counter shaft is lubricated from the clutch housing end through splashed oil from the differential assembly.
Power Flow
Neutral: In neutral, with engine running and clutch engaged, the input shaft turns. With 1st/2nd, 3rd/4th and 5th/Reverse synchronizers in a neutral position, power does not flow to the output shaft.
1st Gear: In 1st gear range, the 3rd/4th and 5th/Reverse synchronizers are in neutral and the 1st/2nd synchronizer sleeve is moved toward the 1st gear blocking ring and 1st gear on the counter shaft (2). Because the 1st/2nd
synchronizer hub is splined to the counter shaft, torque is transmitted from the input shaft 1st gear (1) through the counter shaft 1st gear (2), the synchronizer sleeve and hub, counter shaft 3rd gear (4), output shaft 3rd gear (9),
and into the differential, final drive, assembly.
2nd Gear: In 2nd gear range, the 3rd/4th and 5th/Reverse synchronizers are in neutral and the 1st/2nd synchronizer sleeve is moved toward the 2nd gear blocking ring and 2nd gear on the counter shaft (3). Because
the 1st/2nd synchronizer hub is splined to the counter shaft, torque is transmitted from the input shaft 2nd gear (11) through the counter shaft 2nd gear (3), the synchronizer sleeve and hub, counter shaft 3rd gear (4), output shaft 3rd
gear (9), and into the differential, final drive, assembly.
3rd Gear: In 3rd gear range, the 1st/2nd and 5th/Reverse synchronizers are in neutral, and the 3rd/4th synchronizer sleeve is moved toward the 3rd gear blocking ring and 3rd gear on the input shaft (6). Because the 3rd/4th
synchronizer hub is splined to the input shaft, torque is transmitted from the input shaft through the synchronizer hub and sleeve, 3rd drive gear (6), 3rd driven gear (9), the output shaft, and into the differential, final drive, assembly.
4th Gear: In 4th gear range, the 1st/2nd and 5th/Reverse synchronizers are in neutral and the 3rd/4th synchronizer sleeve is moved toward the 4th gear blocking ring and 4th gear on the input shaft (7). Because the
3rd/4th synchronizer hub is splined to the input shaft, torque is transmitted from the input shaft through the synchronizer hub and sleeve, 4th drive gear (7), 4th driven gear (8), the output shaft, and into the differential, final drive, assembly.
5th Gear: In 5th gear range, the 1st/2nd and 3rd/4th synchronizers are in neutral and the 5th/Reverse synchronizer sleeve is moved toward the 5th gear blocking ring and 5th gear on the output shaft (10). Because the 5th/Reverse
synchronizer hub is splined to the output shaft, torque is transmitted from the input shaft through the 5th drive gear (5), 5th driven gear (10), the synchronizer sleeve and hub, the output shaft, and into the differential, final drive, assembly.
Reverse: In reverse range, the 1st/2nd and 3rd/4th synchronizers are in neutral, and the 5th/Reverse synchronizer sleeve is moved toward the reverse gear blocking ring and the reverse gear on the output shaft (12). Because the
5th/Reverse synchronizer hub is splined to the output shaft, torque is transmitted from the input shaft through the input shaft 1st drive gear (1), counter shaft 1st gear (2), freewheeling as a reverse idler, reverse driven gear (12), the
synchronizer sleeve and hub, the output shaft, and into the differential, final drive, assembly.
