GM 5SPD (Isuzu 76mm) Passenger Exc.Nova

5-Speed Transaxle - Disassembled View:

5-Speed Transaxle - Legend:

Shift Linkage:

Shift Linkage Legend:

5-Speed Transaxle - Cross Section:

5-Speed Transaxle - Differential Gears:

The five-speed transaxle assembly is a constant-mesh design transmission, combined with a differential unit and assembled in a case with a rear cover. All forward gears are in constant mesh. For ease of shifting and selection of the desired gear range, synchronizers with blocker rings, controlled by shift forks are used. Reverse uses a sliding idler gear arrangement.

Fundamental components of these units are the aluminum transaxle case, aluminum clutch housing, aluminium rear cover, input gear (shaft) output gear (shaft), and the differential assembly. The input gear, output gear and differential are all supported by tapered roller bearings. Selective shims are used behind the rear bearing outer races to establish the correct preload.

The final output gear (an integral part of the output shaft) turns the ring gear and differential assembly, thereby turning the drive axle which are attached to the front wheels.

The differential is a conventional arrangement of gears that divides the torque between the drive axles
and allows them to rotate at different speeds. A basic differential consists of a set of four gears.

Two are called differential side gears, and two are differential pinion gears. Each side gear is splined to a drive axle which must turn when its side gear rotates.

The differential pinion gears are mounted on a differential pinion shaft, and the gears are free to rotate on this shaft. The pinion shaft is fitted into a bore in the differential case is at right angles to the drive axles.

Transaxle to engine attachment is accomplished with six (6) bolts, five passing through the transaxle clutch housing and into engine bosses while one attachment on the back side of the engine screws into a transaxle boss.

Two shift cable assemblies are utilized to shift the gears, one being the trans-selector cable and the other a trans-shifter cable.

The routing of the shift cables is forward through the front of the cowl, where a grommet and retainer holds them in place, and anchored to a bracket on the transaxle. The inner cables are attached to the trans control levers with a snap-together ball joint assembly.

The transaxle has an inhibitor built into the shift linkage to prevent a shift from 5th gear into reverse.