Yep, Here are some pictures how I have dismantled the manual transmission.

Remove the transmission from your car as per your shop manual’s instructions. Thoroughly clean the exterior. After the transmission is clean you can look for the transmission code and VIN numbers stamped into the case. If the last 6 digits of your VIN number match the last 6 digits stamped on the transmission case, you have the original transmission for your Corvette. This was in our case. We have a genuine manual speed.

At the end of this article are diagram pictures of the transmission. I’ve used this for the overview.

01_remove_cover_bolts

Drain the transmission then remove the 9 bolts that hold the side cover in place. Carefully remove the cover and shifting forks.

02_cover

The shifter fork of the 1rst and 2nd gear is still in place.

03_cover_removed

Mark the shifting forks with their corresponding clutch assemblies. Also make sure you mark which end of the fork was at the top of the clutch assembly. These forks wear with the clutch assembly as they move back and forth so you want them to stay with their respective clutch assemblies.

04_fork_labeling

Remove the retaining bolt and clip and pull the speedometer gear out of the tailshaft of the transmission.

05_speedometer

With the speedometer gear removed check for any worn, broken, cracked, chipped or flattened teeth. If you find any, replace the gear.

06_speedometer

Drive out the lock pin from the reverse shifter boss. (Look carefully at the end of the pin. You will see that one end is thicker than the other and can only be removed in one direction. Drive the pin out from the bottom of the boss to the top.) THE DIRECTION IN THE PICTURE IS WRONG. It must be done in the opposite direction.

07_pin_reverse

Pull the shifter shaft out partially to disengage the fork from the reverse gear. Screw a nut on the thread to protect it. Use something to pull. I’ve used a hammer to do the Job. Whatever you do, don’t damage the threads.

08_reverselever

Remove the 5 bolts that attach the tailshaft to the transmission main case.

09_remove_extension

Use a soft blow hammer to tap the tailshaft rearward until the reverse idler shaft is clear of the reverse idler gears.

10_remove_extension

Now rotate the tailshaft to the left. Turn the reverse shifter shaft to free the fork from the gear and remove the tailshaft. Clean off any of the old gasket.

11_remove_extension

And here is the result. When the tailshaft is removed, the inner reverse gear will come loose in the remaining housing.

12_remove_extension

The reverse gear is below in the picture. We need an extra gear to be able to reverse the direction of course. This is the one…

13_shimm_reverse

Remove the thrust washer from the left side of the gear. This will be replaced with the rebuild kit.

14_shimreverse_remove

After taking of the reverse gear of the extension housing, the thrust washer is visible. Take it off and look at the notch. This should fit in the recess in the extension housing. This one will be replaced as well.

15_reverse_side_washer

Now the extension housing is taken off. (note: the reverse gear and thrust washer are still there)

16_extension_removed

Now it’s time for an overall picture.

17_overview

Remove the speedometer gear outer snap ring and then tap or slide the gear off the shaft. The second snap ring can now be removed. Here you can see the snap rings and gear are removed from their position on the shaft. Measure the thickness of the rings. In the rebuild kit are several rings with different thicknesses.

Note: On the left of the speedometer gear is the reverse gear.

18_odometer_gear

This is what happens, when the gears are rotating and the reverse gear is engaged. Rounding off teeth is the result. I’ve decided to reuse the gear. Since it is there for 32 years and it takes for ever to grind it off completely.

19_reverse_gear

Remove the 4 input shaft collar retaining bolts and gasket from the front of the transmission. You may need a soft blow hammer to tap it loose.

20_front bearing

And again the work is progressing.

21_cover_removed

Now remove the front bearing snap rings and washer.

22_rem_clips_ring

Here is a detail of the snap ring and washer.

23_clip_removed

I’ve also taken off the snapring on the side of the extrension housing.

24_rem_clip_ring_rear

To remove the front bearing I’ve made a dedicated alluminium puller. The removal of this bearing took me two days. This was realy a pain in the @ss. But finally with penatrating oil and Dutch mucle power the bearing lost its battle.

The snapring in not removed in this case.

25_bearing_puller

Here is how the puller works. There are several pullers which can be used.

26_bearing_pulling

Next remove the rear retainer lock bolts.

27_rem_rear_cover

Tap the rear retiner loose with a soft hammer.

28_rem_rear_cover

Now is a good time to take out the reverse gear out of the main case.

30_remove_reversegear

Carefully slide the input shaft out of the case. The inside of the shaft is full of roller bearings so be careful during removal or you will be chasing these bearings all over the shop floor. The roller bearings will be replaced.

31_0_mainshaft_overview

Here is detail picture #1 of the complete assembly of the main shaft. After reassembling it should look like this.

31_overview_mainshaft

Detail picture #2. On the left the 4th grear. The next one is the 3rd gear. The 4th gear is actually fixing the inputshaft to the output shaft. The Ratio is then 1:1.

32_overview_mainshaft_detail

Detail picture #3. On the left 3rd gear, and then the 2nd gear.

33_overview_mainshaft_detail

Detail picture #4. The hub for the 2nd and the 1rst gear. (seen from left to right).

32_overview_mainshaft_detail

Detail picture #5. The first gear.

35_overview_mainshaft_detail

Use a dummy shaft to drive out the shaft of the countergear. I’ve positioned the housing and the shaft on top of a hole in my table. It’s convenient sometimes. Most of the times it is annoying. The countergear shaft will be replaced. Take care of the woodruff key which will fall out. This key will hold the counter gearshaft in its position (axial and rotational)

36_rem_countergear_axle

And here is the counter gear. It is made out of one piece. Note the type of thrust washers in the sides. Thes will be replaced as well. As soon as it is loose the needles will find it’s way to freedom after a long time in prison.

37_countergear

A detail of a ring (there are more of them, se assembly section) this will hold the needles in place and prevent it from moving in axial direction.

38_countergear_needlebearing

In the middle of the 4 needle bearing sets is a metal distance tube.

39_countergear_assy

This is the input shaft also called the prise shaft. This gear will power the couter gear shaft and it is functioning as the 4th gear. Remember the 1:1 ratio.
There are 16 Needle rollers. They will be replaced as well.

40_needles_inputshaft

Carefully check this area of the mainshaft. It rides in the input shaft. If it has pits, scores, gouges, knicks or grooves, the mainshaft will have to be replaced. Mine was ok. Well you can’t hurt the gearbox with only 165HP duh.

41_bearing_detail_mainshaft

Here is a detail of proof.

42_bearing_detail_mainshaft

Remove the snap ring from the end of the mainshaft. (Tip: measure the thickness)

43_rem_clip_ms

Remove the slide the washer

44_rem_shifter

Then the synchronizer and clutch assembly, synchronizer ring …..

45_detail_synchro

and 3rd gear from the mainshaft.

46_gear_x_rem

Support the rear bearing retainer (make sure it is evenly supported, so it can’t bend) in a press and press the mainshaft out of the bearing. The remaing gears to be removed are inside the press.

47_press_mainshaft

The result.

48_result

Remove the rear bearing to rear retainer snap ring and remove the bearing from the plate. A simple but clever system.

49_remove_bearing_cover

This is the assembly which has to be removed.

50_overview_mainshaft

Fist take off the thrust washer.

51_rem_thrustwasher

Here is the (indexing) key of the hub assembly. These have to be replaced with the new ones. Mines weren’t bad but new ones came with the rebuild kit.

Note that the first gear is taken off.

52_key_position

This is how it looks like when it is installed,

53_key_position

To take off the 2nd gear it was inpossible to do it by hand, so again the press was very usefull.

54_key_holder_rem

Here the 2nd gear is pressed off again in a hydrailic press. Cardboard is used to preventdamages.

55_press_off_gears

56_gears_pressed_off

Everything is bagged and tagged. Make as much as pictures as possible and use a separate bag for each component. At the end you have a big pile of parts.

57_bunch_of_crap

Now everything is dismanteled. Time to look at the housing.

58_naked_shaft

This was one of the main reason to rebuild the gearbox. The endseal went incontinent.

Use a prying tool to remove the seal.

59_sealing_rem

Use a brass hammering tool to hammer out the bushing. This way the housing is not damaged.

60_bushing_rem

And here is the carcas after the crime.

61_bushing_rem

The rebuildkit contains everything you need:

  • Gaskets
  • All types of bearings, needles
  • Synchronising rings an keys
  • Washers
  • Oil seal ring
  • Countergear shaft
  • Snaprings

62_rebuildkit

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