M/T Mainshaft Assembly Clearance Inspection

NOTE: If replacement is required, always replace the synchro sleeve and hub as a set.

1.Support the bearing inner race with an appropriate sized socket (A), and push down on the mainshaft (B).

 

2.Measure the clearance between 2nd gear (C) and 3rd gear (D) with a feeler gauge (E).

  • If the clearance is more than the service limit, go to 3.
  • If the clearance is within the service limit, go to 4.

Standard: 0.06-0.19 mm (0.002-0.007 in.) 
Service Limit: 0.3 mm (0.01 in.) 

3.Measure the thickness of 3rd gear.

  • If the thickness is less than the service limit, replace 3rd gear.
  • If the thickness is within the service limit, replace the 3rd/4th synchro hub/sleeve.

Standard: 23.89-23.97 mm (0.941-0.944 in.) 
Service Limit: 23.8 mm (0.94 in.) 

 

4.Measure the clearance between 4th gear (A) and the distance collar (B) with a dial indicator (C). If the clearance is more than the service limit, go to 5.

Standard: 0.06-0.19 mm (0.002-0.007 in.) 
Service Limit: 0.3 mm (0.01 in.) 

 

5.Measure distance (1) on the 4th gear side distance collar.

  • If distance (1) is not within the standard, replace the distance collar.
  • If distance (1) is within the standard, go to 6.

Standard: 22.53-22.58 mm (0.887-0.889 in.) 

 

6.Measure the thickness of 4th gear.

  • If the thickness is less than the service limit, replace 4th gear.
  • If the thickness is within the service limit, replace the 3rd/4th synchro hub/sleeve.

Standard: 22.39-22.47 mm (0.881-0.885 in.) 
Service Limit: 22.3 mm (0.88 in.) 

 

7.Measure the clearance between the distance collar (A) and 5th gear (B) with a dial indicator (C). If the clearance is more than the service limit, go to 8.

Standard: 0.06-0.19 mm (0.002-0.007 in.) 
Service Limit: 0.3 mm (0.01 in.) 

 

8.Measure distance (2) on the 5th gear side distance collar.

  • If distance (2) is not within the standard, replace the distance collar.
  • If distance (2) is within the standard, go to 9.

Standard: 22.53-22.58 mm (0.887-0.889 in.) 

 

9.Measure the thickness of 5th gear.

  • If the thickness is less than the service limit, replace 5th gear.
  • If the thickness is within the service limit, replace the 5th/6th synchro hub/sleeve.

Standard: 22.39-22.47 mm (0.881-0.885 in.) 
Service Limit: 22.3 mm (0.88 in.) 

 

10.Measure the clearance between 6th gear (A) and the angular ball bearing inner race (B) with a dial indicator (C). If the clearance is more than the service limit, go to 11.

Standard: 0.06-0.19 mm (0.002-0.007 in.) 
Service Limit: 0.3 mm (0.01 in.) 

 

11.Measure the thickness of the distance collar.

  • If the thickness is less than the standard, replace the distance collar.
  • If the thickness is within the standard, go to 12.

Standard: 22.03-22.08 mm (0.867-0.869 in.) 

 

12.Measure the thickness of 6th gear.

  • If the thickness is less than the service limit, replace 6th gear.
  • If the thickness is within the service limit, replace the 5th/6th synchro hub/sleeve.

Standard: 21.89-21.97 mm (0.862-0.865 in.) 
Service Limit: 21.8 mm (0.86 in.)