Transmission Unit
A760H AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION UNIT: INSPECTION
1. INSPECT 1ST AND REVERSE BRAKE RETURN SPRING SUB-ASSEMBLY
(a) Using a vernier caliper, measure the free length of the spring together with the spring seat.
Standard free length:
23.74 mm (0.935 in.)
If the free length is shorter than the standard free length, replace the brake piston return spring sub-assembly.
2. INSPECT REAR PLANETARY GEAR ASSEMBLY
(a) Using a feeler gauge, measure the rear planetary gear pinion thrust clearance.
Standard clearance:
0.2 to 0.6 mm (0.008 to 0.024 in.)
If the clearance is greater than the standard clearance, replace the planetary gear assembly.
(b) Using a dial indicator, measure the inside diameter of the rear planetary gear bushing.
Standard inside diameter:
20.025 mm (0.7884 in.)
If the inside diameter is greater than the standard inside diameter, replace the rear planetary gear assembly.
3. INSPECT PACK CLEARANCE OF 1ST AND REVERSE BRAKE PISTON
(a) Make sure that the 1st and reverse brake piston moves smoothly when pulling and releasing the compressed air gun lever while applying compressed air into the transmission case.
(b) Using a vernier caliper, measure the level difference (dimension A) between the upper surface of the brake apply tube and the contact surface of the No. 4 brake flange at both ends across the 1st and reverse brake piston diameter, and calculate the average.
NOTICE:
The 1st and reverse brake piston must be securely installed to the end face of the transmission case.
HINT
Dimension A = 22.05 to 22.91 mm (0.8681 to 0.9020 in.)
(c) Using a vernier caliper, measure the thickness (dimension B) of the brake flanges, the 4 No. 4 brake plates and the 4 No. 4 brake discs altogether at both ends across a diameter, and calculate the average.
HINT
Dimension B = 23.11 to 23.89 mm (0.9098 to 0.9405 in.)
Pack Clearance = Dimension A - Dimension B - 0.22 mm (0.0087 in.) + 1.8 mm (0.071 in.)
Pack Clearance:
0.4 to 0.7 mm (0.016 to 0.028 in.)
(d) If the pack clearance is outside the standard range, select and install a brake flange that brings the pack clearance to be within the standard range.
HINT
There are 8 types of flanges that can be used to adjust the pack clearance. Select the one with the most appropriate thickness.
Thickness H:
4. INSPECT NO. 4 BRAKE DISC
(a) Check whether the sliding surfaces of the discs, the plates, and the flange are worn or burnt.
If necessary, replace them.
NOTICE:
* If the linings of the discs are peeled off or discolored, or if any part of the printed numbers is damaged, replace all discs.
* Before assembling new discs, soak them in ATF for at least 15 minutes.
5. INSPECT INTERMEDIATE SHAFT
(a) Using a dial indicator, check the intermediate shaft runout.
Standard runout:
A
0.03 mm (0.0012 in.)
B
0.03 mm (0.0012 in.)
C
0.03 mm (0.0012 in.)
D
0.03 mm (0.0012 in.)
If the runout exceeds the specification, replace the intermediate shaft with a new one.
(b) Using a micrometer, check the outer diameter of the intermediate shaft at each point shown in the illustration.
Standard diameter:
A
25.962 to 25.975 mm (1.022 to 1.023 in.)
B
25.962 to 25.975 mm (1.022 to 1.023 in.)
C
32.062 to 32.075 mm (1.262 to 1.263 in.)
D
32.062 to 32.075 mm (1.262 to 1.263 in.)
If the outer diameter is outside the standard range, replace the intermediate shaft with a new one.
6. INSPECT REAR PLANETARY RING GEAR FLANGE SUB-ASSEMBLY
(a) Using a dial indicator, measure the inside diameter of the rear planetary ring gear bushing.
Standard inside diameter:
32.19 mm (1.2673 in.)
If the inside diameter is greater than the standard inside diameter, replace the rear planetary ring gear.
7. INSPECT NO. 3 ONE WAY CLUTCH ASSEMBLY
(a) Hold the rear planetary ring gear flange sub-assembly and turn the one way clutch assembly.
(b) Check that the one way clutch assembly turns freely counterclockwise and locks clockwise.
If there is a problem with the one way clutch, replace the one way clutch.
8. INSPECT CENTER PLANETARY GEAR ASSEMBLY
(a) Using a feeler gauge, measure the center planetary gear pinion thrust clearance.
Standard clearance:
0.12 to 0.68 mm (0.005 to 0.027 in.)
If the clearance is greater than the standard clearance, replace the center planetary gear assembly.
9. INSPECT NO. 2 BRAKE DISC
(a) Check whether the sliding surfaces of the discs, the plates, and the flange are worn or burnt.
If necessary, replace them.
NOTICE:
* If the linings of the discs are peeled off or discolored, or if any part of the printed numbers is damaged, replace all discs.
* Before assembling new discs, soak them in ATF for at least 15 minutes.
10. INSPECT NO. 2 BRAKE PISTON RETURN SPRING SUB-ASSEMBLY
(a) Using a vernier caliper, measure the free length of the spring together with the spring seat.
Standard free length:
for 4GR-FSE
17.45 mm (0.687 in.)
for 2GR-FSE
22.66 mm (0.892 in.)
If the free length is shorter than the standard free length, replace the No. 2 brake piston return spring sub-assembly.
11. INSPECT PISTON STROKE OF NO. 2 BRAKE PISTON (for 4GR-FSE)
(a) Inspect the piston stroke of the No. 2 brake piston.
(1) Make sure that the No. 2 brake piston moves smoothly when pulling and releasing the compressed air gun lever while applying compressed air into the transmission case.
(2) Using SST and a dial indicator, measure the moving distance (distance A) of the clutch disc at both ends across a diameter while blowing air from the oil hole as shown in the illustration, and calculate the average.
SST : 09350-30020
09350-06120
Piston Stroke:
0.45 to 0.75 mm (0.0177 to 0.0295 in.)
(3) If the piston stroke is outside the standard range, select and install a brake flange that brings the piston stroke within the standard range.
HINT
There are 11 types of flanges that can be used to adjust the pack clearance. Select one with the most appropriate thickness.
Flange thickness:
12. INSPECT PISTON STROKE OF NO. 2 BRAKE PISTON (for 2GR-FSE)
(a) Inspect the piston stroke of the No. 2 brake piston.
(1) Make sure that the No. 2 brake piston moves smoothly when pulling and releasing the compressed air gun lever while applying compressed air into the transmission case.
(2) Using SST and a dial indicator, measure the moving distance (distance A) of the clutch disc at both ends across a diameter while blowing air from the oil hole as shown in the illustration, and calculate the average.
SST : 09350-30020
09350-06120
Piston Stroke:
0.6 to 0.9 mm (0.0236 to 0.0354 in.)
(3) If the piston stroke is outside the standard range, select and install a brake flange that brings the piston stroke within the standard range.
HINT
There are 8 types of flanges that can be used to adjust the pack clearance. Select one with the most appropriate thickness.
Flange thickness:
13. INSPECT BRAKE PISTON RETURN SPRING SUB-ASSEMBLY
(a) Using a vernier caliper, measure the free length of the spring together with the spring seat.
Standard free length:
17.05 mm (0.671 in.)
If the free length is shorter than the standard free length, replace the brake piston return spring sub-assembly.
14. INSPECT FRONT PLANETARY GEAR ASSEMBLY
(a) Using a feeler gauge, measure the front planetary pinion gear thrust clearance.
Standard clearance:
0.20 to 0.60 mm (0.008 to 0.024 in.)
If the clearance is greater than the standard clearance, replace the front planetary gear assembly.
(b) Using a dial indicator, measure the inside diameter of the front planetary gear bushing.
Standard inside diameter:
57.43 mm (2.261 in.)
If the inside diameter is greater than the standard inside diameter, replace the front planetary gear assembly.
15. INSPECT ONE WAY CLUTCH ASSEMBLY
(a) Install the one way clutch assembly to the one way clutch inner race.
(b) Hold the one way clutch inner race and turn the one way clutch assembly.
(c) Check that the one way clutch assembly turns freely counterclockwise and locks clockwise.
If there is a problem with the one way clutch, replace the one way clutch.
(d) Remove the one way clutch assembly from the one way clutch inner race.
16. INSPECT PISTON STROKE OF NO. 1 BRAKE PISTON
(a) Inspect the piston stroke of the No. 1 brake piston.
(1) Make sure that the No. 1 brake piston moves smoothly when pulling and releasing the compressed air gun lever while applying compressed air into the transmission case.
(2) Using a vernier caliper, measure the level difference (dimension A) between the upper surface of the No. 1 brake piston and the contact surface of the No. 1 brake flange at both ends across the No. 1 brake piston diameter.
(3) Using a vernier caliper, measure the thickness (dimension B) of the brake flange, the 3 No. 1 brake plates and the 3 No. 1 brake discs altogether at both ends across a diameter, and calculate the average.
HINT
Dimension A = 15.29 to 15.77 mm (0.6020 to 0.6209 in.)
Dimension B = 14.72 to 15.12 mm (0.5795 to 0.5953 in.)
Piston stroke = Dimension A - Dimension B
Piston stroke:
0.42 to 0.72 mm (0.017 to 0.028 in.)
If the piston stroke is outside the specified range, parts may have been assembled incorrectly, so check and reassemble them again.
If the piston stroke is still outside the specified range, select another flange that brings the piston stroke within the specified range.
HINT
There are 4 different thicknesses for the flange.
Flange thickness:
17. INSPECT NO. 1 BRAKE DISC
(a) Check whether the sliding surfaces of the discs, the plates or the flange are worn or burnt.
If necessary, replace them.
NOTICE:
* If the linings of the discs are peeled off or discolored, or if any part of the groove is damaged, replace all discs.
* Before assembling new discs, soak them in ATF for at least 15 minutes.
18. INSPECT NO. 3 BRAKE PISTON RETURN SPRING SUB-ASSEMBLY
(a) Using a vernier caliper, measure the free length of the spring together with the spring seat.
Standard free length:
15.72 mm (0.619 in.)
If the free length is shorter than the standard free length, replace the No. 3 brake piston return spring sub-assembly.
19. INSPECT NO. 3 BRAKE DISC
(a) Check whether the sliding surfaces of the discs, the plates or the flange are worn or burnt.
If necessary, replace them.
NOTICE:
* If the linings of the discs are peeled off or discolored, or if any part of the printed numbers is damaged, replace all discs.
* Before assembling new discs, soak them in ATF for at least 15 minutes.
20. INSPECT NO. 2 ONE WAY CLUTCH ASSEMBLY
(a) Hold the reverse clutch hub and turn the No. 2 one way clutch assembly.
(b) Check that the No. 2 one way clutch assembly turns freely clockwise and locks counterclockwise.
If there is a problem with the one way clutch, replace the one way clutch.
21. INSPECT INDIVIDUAL PISTON OPERATION
(a) Check the operating sound while applying compressed air into the oil holes indicated in the illustration.
HINT
When inspecting the clutch drum and input shaft, check the operating sound with the C3 accumulator piston hole closed.
If there is no sound, disassemble and check the installation condition of the parts.
(1) No. 2 Clutch (C2)
(2) No. 4 Clutch (C4)
(3) No. 3 Clutch (C3)
(4) No. 1 Clutch (C1)
(5) No. 3 Brake (B3)
(6) No. 1 Brake (B1)
(7) No. 2 Brake (B2)
(8) No. 4 Brake (B4)