Before assembling, lubricate all parts of the gearbox to prevent scuffing during the initial period of operation

Smear the threaded part of the bolts with paint before setting

Only new gaskets and seals are installed during assembly.

Assemble the gearbox in the reverse order of disassembly. In this case, the following should be taken into account.

Punching the ball bearing fastening nut for the GAZ-53 gearbox, GAZ-66

Assemble the drive shaft and third gear with the synchronizer locking rings.

When assembling, the following must be provided:

  • - the area of ​​contact of the ring to the shaft is not less than 70% of the surface of the cone of the drive shaft;
  • - gap between the ends of the spur ring of the drive shaft and the blocking ring within 0.8-1.25 mm;
  • - if necessary, grind the conical surfaces of the shaft and ring; tighten the nut for fastening the ball bearing of the drive shaft (torque 30 kGm) and center it over the groove of the shaft (Fig. 1).

Pick up the sliding gear of the first gear and reverse gear along the splines of the driven shaft.

Selection should ensure that there is no noticeable angular play when the gear slides freely along the splines of the shaft.

Angular backlash on the splines should be no more than 0.18 mm when checking at the radius of the pitch circle of the gear.

The axial play of the first gear and reverse gear on the shaft during selection should be no more than 0.05 mm when measured at a radius of 75 mm.

After selecting, mark the location of the slots of the mating parts with paint.

Synchronizer Assembly

Pick up the clutch according to the splines of the synchronizer hub. This selection should provide:

  • - side clearance within 0 - 0.01 mm and easy movement of parts without noticeable side clearance;
  • - the longitudinal play of the coupling in its extreme positions is not more than 0.2 mm and the runout of the ends of the groove for the shift fork is not more than 0.18 mm when checking on a slotted mandrel

Pressing a sliding sleeve with a hub onto the driven shaft

In fig. 2 shows the installation of crackers and the synchronizer spring, and in fig. 3 - pressing the sliding sleeve with the hub onto the driven shaft

When assembling the reverse rod head, turn the spring stopper flush with the end of the housing and center it at four points.

Press the axle of the reverse gear unit flush with the surface of the rear wall of the crankcase.

Install the axle of the block so that if you look at the end of the axle from behind (along the direction of the car), then its flats would be turned towards the intermediate shaft and located symmetrically relative to the horizontal axis of the block. There are no flats on some of the cars.

Press the intermediate shaft front bearing cap onto the sealing paste flush with the crankcase front wall.

Installing the intermediate shaft ball bearing Installing the drive shaft of the GAZ-66, GAZ-53 gearbox

Turn the intermediate shaft ball bearing fastening nut (torque 25 kGm) and center it over the shaft groove. The fitting of this bearing is shown in fig. 4.

When installing the drive shaft (fig. 5) in the hole in the gearbox housing, make sure that the notch on the spur and the shaft cone is at the bottom.

Press the output shaft seal flush with the outer end of the cover.

Tighten the flange fastening nut on the driven shaft (torque 25 kgm).

Gearbox puller

The tool for assembling and disassembling the gearbox is shown in fig. 6.

Put the assembled gearbox on the stand and test it without load at a rotation speed of 750 rpm of the driven shaft for one minute without adding oil for noise, heating and ease of shifting in all gears.

Installing a gearbox on a GAZ-53A car

Using a lifting tool, install the gearbox onto the clutch housing.

Install the ventilation hatch on the right side of the clutch housing.

Install the lubricator cap of the clutch bearing (the bearing assembly with the coupling and the lubricator cap hose is installed before installing the box).

Put the plug off clutch.

Install and cotter the clutch release fork rod.

Install the fork return spring.

Adjust the length of the clutch release fork rod.

Install the handbrake lever assembly.

Connect the handbrake rod to the lever on the box,

Adjust the handbrake.

Fix the propeller shaft intermediate support.

Connect the flanges of the cardan shaft and the driven shaft of the gearbox.

Connect the speedometer cable.

Fill the gearbox with oil.

Install the transmission cover.

Install the gear lever.

Install the protective cap of the top cover.

Install the cab floor mat.

The gearbox on the GAZ-b6 car is installed in the reverse order of its removal.