Automatic Transmission Unit: Inspection
- INSPECT 1ST AND REVERSE BRAKE RETURN SPRING SUB-ASSEMBLY
- Using vernier calipers, 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.
- Using vernier calipers, measure the free length of the spring together with the spring seat.
- INSPECT REAR PLANETARY GEAR ASSEMBLY
- 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.
- 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.
- Using a feeler gauge, measure the rear planetary gear pinion thrust clearance.
- INSPECT PACK CLEARANCE OF 1ST AND REVERSE BRAKE PISTON
- 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.
- Using vernier calipers, measure the level difference (dimension A) between the upper surface of the brake apply tube and the hitting surface of the No. 4 brake flange at both ends across the 1st and reverse brake piston diameter, and calculate the average.NOTE: 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.)
- Using vernier calipers, 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.)
- 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
FLANGE THICKNESS SPECIFICATIONNO. Thickness H NO. Thickness H 0 0 mm (0 in.) 8 0.8 mm (0.03150 in.) 2 0.2 mm (0.00787 in.) 10 1.0 mm (0.03937 in.) 4 0.4 mm (0.01575 in.) 12 1.2 mm (0.04724 in.) 6 0.6 mm (0.02362 in.) 14 1.4 mm (0.05512 in.)
- INSPECT NO. 4 BRAKE DISC
- Check whether the sliding surfaces of the discs, the plates, and the flange are worn or burnt. If necessary, replace them.
- INSPECT INTERMEDIATE SHAFT
- 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.
- 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.
- Using a dial indicator, check the intermediate shaft runout.
- INSPECT REAR PLANETARY RING GEAR FLANGE SUB-ASSEMBLY
- 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.
- Using a dial indicator, measure the inside diameter of the rear planetary ring gear bushing.
- INSPECT NO. 3 ONE WAY CLUTCH ASSEMBLY
- Hold the rear planetary ring gear flange sub-assembly and turn the one way clutch assembly.
- 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.
- INSPECT CENTER PLANETARY GEAR ASSEMBLY
- 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.
- Using a feeler gauge, measure the center planetary gear pinion thrust clearance.
- INSPECT NO. 2 BRAKE DISC
- Check whether the sliding surfaces of the discs, the plates, and the flange are worn or burnt. If necessary, replace them.
- INSPECT NO. 2 BRAKE PISTON RETURN SPRING SUB-ASSEMBLY
- Using vernier calipers, measure the free length of the spring together with the spring seat.
Standard free length:
22.66 mm (0.8921 in.)
If the free length is shorter than the standard free length, replace the No. 2 brake piston return spring sub-assembly.
- Using vernier calipers, measure the free length of the spring together with the spring seat.
- INSPECT NO. 2 BRAKE PISTON
- Inspect piston stroke of the No. 2 brake piston.
- 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.
- Using SST and a dial indicator, measure the moving distance (dimension 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 (0.024 to 0.035 in.)
- 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 piston stroke. Select one with the most appropriate thickness.
Flange thickness
FLANGE THICKNESS SPECIFICATIONNo. Thickness 0 2.0 mm (0.079 In.) 1 2.1 mm (0.083 in.) 2 2.2 mm (0.087 in.) 3 2.3 mm (0.091 in.) 4 2.4 mm (0.094 in.) 5 2.5 mm (0.098 in.) 6 2.6 mm (0.102 in.) 7 2.7 mm (0.106 in.)
- Inspect piston stroke of the No. 2 brake piston.
- INSPECT BRAKE PISTON RETURN SPRING SUB-ASSEMBLY
- Using vernier calipers, 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.
- Using vernier calipers, measure the free length of the spring together with the spring seat.
- INSPECT FRONT PLANETARY GEAR ASSEMBLY
- 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.
- 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 maximum inside diameter, replace the front planetary gear assembly.
- Using a feeler gauge, measure the front planetary pinion gear thrust clearance.
- INSPECT ONE WAY CLUTCH ASSEMBLY
- Install the one way clutch assembly to the one way clutch inner race.
- Hold the one way clutch inner race and turn the one way clutch assembly.
- 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.
- Remove the one way clutch assembly from the one way clutch inner race.
- INSPECT NO. 1 BRAKE PISTON
- Inspect piston stroke of the No. 1 brake piston.
- 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.
- Using vernier calipers, measure the level difference (dimension A) between the upper surface of the No. 1 brake piston and the hitting surface of the No. 1 brake flange at both ends across the No. 1 brake piston diameter.
- Using vernier calipers, measure the thickness (dimension B) of the brake flange, the 3 No. 1 brake plates and the 3 No. 1 brake discs altogether at the 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.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
If the piston stroke is not 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 that bring the piston stroke within the specified range.
Flange thickness
FLANGE THICKNESS SPECIFICATIONNo. Thickness 0 2.0 mm (0.079 in.) 1 2.2 mm (0.087 in.) 2 2.4 mm (0.094 in.) 3 2.6 mm (0.102 in.)
- Inspect piston stroke of the No. 1 brake piston.
- INSPECT NO. 1 BRAKE DISC
- Check whether the sliding surfaces of the discs, the plates, or the flange are worn or burnt. If necessary, replace them.
- INSPECT NO. 3 BRAKE PISTON RETURN SPRING SUB-ASSEMBLY
- Using vernier calipers, measure the free length of the spring together with the spring seat.
Standard free length:
15.72 mm (0.619 in.)
If the inside diameter is shorter than the standard free length, replace the No. 3 brake piston return spring sub-assembly.
- Using vernier calipers, measure the free length of the spring together with the spring seat.
- INSPECT 2ND BRAKE DISC SET
- Check whether the sliding surfaces of the discs, the plates, or the flange are worn or burnt. If necessary, replace them.
- INSPECT NO. 2 ONE WAY CLUTCH ASSEMBLY
- Hold the reverse clutch hub and turn the No. 2 one way clutch assembly.
- 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.
- INSPECT INDIVIDUAL PISTON OPERATION
- Check the operating sound while applying compressed air into the oil holes indicated in the illustration.
HINT:
When inspecting the O/D direct clutch, 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.
- No. 2 Clutch (C2)
- No. 4 Clutch (C4)
- No. 3 Clutch (C3)
- No. 1 Clutch (C1)
- No. 3 Brake (B3)
- No. 1 Brake (B1)
- No. 2 Brake (B2)
- No. 4 Brake (B4)
- Check the operating sound while applying compressed air into the oil holes indicated in the illustration.