450F Backhoe Loader Transmission (Autoshift) Caterpillar

Specifications

Illustration 1	g03235317
Pressure tap locations (1) Clutch pressure for the all wheel drive (2) Clutch 1 (3) Lubrication pressure (4) Reverse clutch (5) Forward low clutch (6) Forward high clutch (7) Regulated pump pressure (8) Clutch 2 (9) Clutch 3

Table 1

Torque Converter Stall Speeds (1)
Minimum RPM	Maximum RPM
2130	2206

( 1 )

Stall speeds are calculated using No. 2 diesel fuel.

Table 2

Transmission Test Pressures
Component/System	Pressure at High Idle	Actual Readings
Regulated Pump Pressure Pressure Tap 7	1500 ± 250 kPa (220 ± 36 psi)
Lubrication Pressure Pressure Tap 3	25 to 300 kPa (4 to 44 psi)
All Wheel Drive Pressure Pressure Tap 1	1500 ± 250 kPa (220 ± 36 psi)

Table 3

Transmission Clutch Test Pressures
Forward Speeds
Gear	Forward Low Clutch Pressure Tap 5	Clutch 1 Pressure Tap 2	Actual Readings
First gear forward at high idle	1350 ± 250 kPa (195 ± 36 psi)	1500 ± 250 kPa (220 ± 36 psi)
Gear	Forward High Clutch Pressure Tap 6	Clutch 1 Pressure Tap 2	Actual Readings
Second speed forward at high idle	1350 ± 250 kPa (195 ± 36 psi)	1500 ± 250 kPa (220 ± 36 psi)
Gear	Forward High Clutch Pressure Tap 6	Clutch 2 Pressure Tap 8	Actual Readings
Third speed forward at high idle	1350 ± 250 kPa (195 ± 36 psi)	1500 ± 250 kPa (220 ± 36 psi)
Gear	Forward Low Clutch Pressure Tap 5	Clutch 3 Pressure Tap 9	Actual Readings
Fourth gear forward at high idle	1350 ± 250 kPa (195 ± 36 psi)	1500 ± 250 kPa (220 ± 36 psi)
Gear	Forward High Clutch Pressure Tap 6	Clutch 3 Pressure Tap 9	Actual Readings
Fifth gear forward at high idle	1350 ± 250 kPa (195 ± 36 psi)	1500 ± 250 kPa (220 ± 36 psi)
Reverse Speeds
Gear	Reverse Clutch Pressure Tap 4	Clutch 1 Pressure Tap 2	Actual Readings
First speed reverse at high idle	1350 ± 250 kPa (195 ± 36 psi)	1500 ± 250 kPa (220 ± 36 psi)
Gear	Reverse Clutch Pressure Tap 4	Clutch 2 Pressure Tap 8	Actual Readings
Second speed reverse gear at high idle	1350 ± 250 kPa (195 ± 36 psi)	1500 ± 250 kPa (220 ± 36 psi)
Gear	Reverse Clutch Pressure Tap 4	Clutch 3 Pressure Tap 9	Actual Readings
Third speed reverse at high idle	1350 ± 250 kPa (195 ± 36 psi)	1500 ± 250 kPa (220 ± 36 psi)
Gear	No test pressures
Neutral

Introduction

The following instruction describes the testing procedure for the Autoshift Transmission.

Note: All testing is performed with the machine at the proper operating temperature.

Required Tools

Table 4

Required Tools
Tool	Item	Qty	Part No	Description
B	B1	1	8T-0853	Pressure Gauge
	B2	6	8T-0855	Pressure Gauge
	B3	7	6V-3965	Fitting
	B4	7	3J-1907	O-Ring Seal (1)
	B5	7	6V-3989	Fitting
	B6	14	6V-4143	Quick Connect Coupler
	B7	7	177-7860	Hose As
C	C1	1	6V-3121	Multitach

( 1 )

Used with the 6V-3965 Fitting (B3)

Assemble the pressure gauge and hose groups as follows.

1. Install one of the 6V-4143 Quick Connect Coupler (B6) onto each end of each 177-7860 Hose As (B7) .

2. Install one 6V-3989 Fitting onto each pressure gauge.

3. Connect one of the 177-7860 Hose As to each of the pressure gauges.

Test Preparation

The following components must be removed before any of the transmission hydraulic system pressure tests can be performed.

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Illustration 2	g03249859

1. Remove two bolts (10) and plate (11) .

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Illustration 3	g03249876

2. Remove two bolts (13) and plate (14). Remove floor mat (12) .

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Illustration 4	g03249877

3. Remove six bolts (15) from the perimeter of the floorplate. Set the floorplate (16) aside.

4. Proceed to the appropriate test that is required. Reinstall the plates, screws, and the mats to the cab when testing is completed.

Test Preparation - Transmission Oil Pump

Illustration 5	g03247921
(7) Regulated pump pressure test port (typical example)

1. Install one 6V-3965 Fitting (B2) and 3J-1907 O-Ring Seal (B3) into the regulated clutch pressure test port (7) .

2. Place the direction control lever in NEUTRAL

3. Activate the parking brake.

4. Start the engine and run the engine at low idle until the engine reaches the proper operating temperature.

Test Procedure - Transmission Oil Pump

1. Run the engine at high idle. Note the pressure reading. The pressure should be 1500 ± 250 kPa (220 ± 36. psi).

2. Reduce engine speed to low idle.

3. Stop engine and remove the test equipment.

Test Preparation - Torque Converter Stall Speed

1. Start the engine and set the throttle at low idle.

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Illustration 6	g03248020

2. Lower the stabilizers and lift the rear wheels about 150 mm (6 inch) off the ground.

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Illustration 7	g03248028

3. Place the bucket hydraulic controls in the lowering position. Lift the front wheels about 150 mm (6 inch) off the ground and support the front axle with suitable jack stands.

4. Stop the engine.

5. Install the 6V-3121 Multitach on the engine.

   ReferenceRefer to Special Instruction, SEHS7807, "Using The 6V2100 Multitach And 6V3121 Multitach Group" for detailed operating instructions for the Multitach.

Test Procedure - Torque Converter Stall Speed

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NOTICE
To ensure that the transmission oil does not overheat, do not keep the torque converter in a full stall condition for more than 30 seconds. After the torque converter stall test, reduce the engine speed to low idle. In order to cool the oil, move the transmission control to the NEUTRAL position and run the engine between 1200 rpm and 1500 rpm.

1. With the transmission shift lever in NEUTRAL, start the engine and set the throttle to low idle.

2. Turn off the air conditioning and any hydraulic functions.

3. Run the engine at high idle.

4. Fully engage the brakes.

5. Run the transmission at normal operating temperature. 59° to 71° C (138° to 160° F).

6. Shift to FOURTH SPEED. Shift the forward/reverse shuttle to FORWARD and stall the torque converter until the temperature of the converter reaches 90° to 93° C (194° to 200° F).

7. Record the stall speed. The stall speed should be between 2130 RPM to 2206 RPM.

   Note: Stall speeds are calculated using No. 2 diesel fuel. Factory fuel may cause the rpm to be lower than the specifications.

8. When the test is complete, put the directional control in NEUTRAL, engage the parking brake, stop the engine and remove the test equipment.

Test Conclusions - Torque Converter Stall Speed

Problem

The oil gets too hot during normal operation.

Probable cause

• Not enough oil is in the torque converter because the inlet relief valve for the torque converter is open.

• The oil pump fails.

• The torque converter fails.

• The temperature gauge is bad. Replace the temperature gauge and the sending unit.

• Debris is blocking air flow to the radiator.

Problem

Stall speed is low.

Probable cause

• There is an engine problem.

• The machine is using factory fuel.

• There is a problem with the torque converter.

• Air conditioning is on or there may be other parasitic loads.

Note: The shifting of the transmission is controlled by the ECM in relation with transmission output speed.

Test Preparation - Forward Clutch Pressure - First Speed

1. Install the 6V-3121 Multitach on the engine.

   ReferenceRefer to Special Instruction, SEHS7807, "Using The 6V2100 Multitach And 6V3121 Multitach Group" for detailed operating instructions for the Multitach.

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Illustration 8	g03249996
(3) Lubrication pressure tap (typical example) (5) Forward low pressure tap (typical example) (6) Forward high pressure tap (typical example)

2. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the forward low clutch pressure tap (5). Connect one of the 8T-0855 Pressure Gauges to the fitting.

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Illustration 9	g03249997
(1) All wheel drive pressure tap (typical example) (2) Clutch one pressure tap (typical example) (3) Lubrication pressure tap (typical example)

3. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the clutch 1 pressure tap (2). Connect one of the 8T-0855 Pressure Gauges to the fitting.

Test Procedure - Forward Clutch Pressure - First Speed

1. Start the engine and set the throttle at low idle. Allow the machine to reach the proper operating temperature.

2. Turn on the autoshift function.

3. With the transmission gear selector in the NEUTRAL position, shift the directional control lever to the FIRST SPEED FORWARD position.

4. Increase the engine speed to high idle.

   The pressure on the gauge for the forward low clutch (5) must be 1350 ± 250 kPa (195 ± 36 psi)

   The pressure on the gauge for the clutch 1 (2) must be 1500 ± 250 kPa (220 ± 36 psi)

5. When the test is complete, put the directional control in NEUTRAL, engage the parking brake, stop the engine and remove the test equipment.

Test Preparation - Forward Clutch Pressure - Second Speed

1. Install the 6V-3121 Multitach on the engine.

   ReferenceRefer to Special Instruction, SEHS7807, "Using The 6V2100 Multitach And 6V3121 Multitach Group" for detailed operating instructions for the Multitach.

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Illustration 10	g03249996
(3) Lubrication pressure tap (typical example) (5) Forward low pressure tap (typical example) (6) Forward high pressure tap (typical example)

2. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the forward high clutch pressure tap (6). Connect one of the 8T-0855 Pressure Gauges to the fitting.

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Illustration 11	g03249997
(1) All wheel drive pressure tap (typical example) (2) Clutch one pressure tap (typical example) (3) Lubrication pressure tap (typical example)

3. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the clutch 1 pressure tap (2). Connect one of the 8T-0855 Pressure Gauges to the fitting.

Test Procedure - Forward Clutch Pressure - Second Speed

1. Start the engine and set the throttle at low idle. Allow the machine to reach the proper operating temperature.

2. Turn on the autoshift function.

3. Shift the directional control lever to the SECOND SPEED FORWARD position.

4. Increase the engine speed to high idle.

5. When the transmission output speed is approximately 365 rpm. the solenoid for the forward high clutch and the solenoid for clutch 1 are energized.

   The pressure on the gauge for the forward high clutch (6) must be 1350 ± 250 kPa (195 ± 36 psi)

   The pressure on the gauge for the clutch 1 (2) must be 1500 ± 250 kPa (220 ± 36 psi)

6. When the test is complete, put the directional control in NEUTRAL, engage the parking brake, stop the engine and remove the test equipment.

Test Preparation - Forward Clutch Pressure - Third Speed

1. Install the 6V-3121 Multitach on the engine.

   ReferenceRefer to Special Instruction, SEHS7807, "Using The 6V2100 Multitach And 6V3121 Multitach Group" for detailed operating instructions for the Multitach.

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Illustration 12	g03249996
(3) Lubrication pressure tap (typical example) (5) Forward low pressure tap (typical example) (6) Forward high pressure tap (typical example)

2. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the forward high clutch pressure tap (6). Connect one of the 8T-0855 Pressure Gauges to the fitting.

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Illustration 13	g03250341
(8) Clutch number two pressure tap (typical example) (9) Clutch number three pressure tap (typical example)

3. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the clutch 2 pressure tap (8). Connect one of the 8T-0855 Pressure Gauges to the fitting.

Test Procedure - Forward Clutch Pressure - Third Speed

1. Start the engine and set the throttle at low idle. Allow the machine to reach the proper operating temperature.

2. Turn on the autoshift function.

3. Shift the directional control lever to the THIRD SPEED FORWARD position.

4. Increase the engine speed to high idle.

5. When the transmission output speed is approximately 630 rpm. the solenoid for the forward high clutch and the solenoid for clutch 2 are energized.

   The pressure on the gauge for the forward high clutch (6) must be 1350 ± 250 kPa (195 ± 36 psi)

   The pressure on the gauge for the clutch 2 (8) must be 1500 ± 250 kPa (220 ± 36 psi)

6. When the test is complete, put the directional control in NEUTRAL, engage the parking brake, stop the engine and remove the test equipment.

Test Preparation - Forward Clutch Pressure - Fourth Speed

1. Install the 6V-3121 Multitach on the engine.

   ReferenceRefer to Special Instruction, SEHS7807, "Using The 6V2100 Multitach And 6V3121 Multitach Group" for detailed operating instructions for the Multitach.

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Illustration 14	g03249996
(3) Lubrication pressure tap (typical example) (5) Forward low pressure tap (typical example) (6) Forward high pressure tap (typical example)

2. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the forward low clutch pressure tap (5). Connect one of the 8T-0855 Pressure Gauges to the fitting.

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Illustration 15	g03250341
(8) Clutch number two pressure tap (typical example) (9) Clutch number three pressure tap (typical example)

3. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the clutch 3 pressure tap (9). Connect one of the 8T-0855 Pressure Gauges to the fitting.

Test Procedure - Forward Clutch Pressure - Fourth Speed

1. Start the engine and set the throttle at low idle. Allow the machine to reach the proper operating temperature.

2. Turn on the autoshift function.

3. Shift the directional control lever to the FOURTH SPEED FORWARD position.

4. Increase the engine speed to high idle.

5. When the transmission output speed is approximately 1225 rpm. the solenoid for the forward low clutch and the solenoid for clutch 3 are energized.

   The pressure on the gauge for the forward low clutch (5) must be 1350 ± 250 kPa (195 ± 36 psi)

   The pressure on the gauge for the clutch 3 (9) must be 1500 ± 250 kPa (220 ± 36 psi)

6. When the test is complete, put the directional control in NEUTRAL, engage the parking brake, stop the engine and remove the test equipment.

Test Preparation - Forward Clutch Pressure - Fifth Speed

1. Install the 6V-3121 Multitach on the engine.

   ReferenceRefer to Special Instruction, SEHS7807, "Using The 6V2100 Multitach And 6V3121 Multitach Group" for detailed operating instructions for the Multitach.

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Illustration 16	g03249996
(3) Lubrication pressure tap (typical example) (5) Forward low pressure tap (typical example) (6) Forward high pressure tap (typical example)

2. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the forward high clutch pressure tap (6). Connect one of the 8T-0855 Pressure Gauges to the fitting.

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Illustration 17	g03250341
(8) Clutch number two pressure tap (typical example) (9) Clutch number three pressure tap (typical example)

3. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the clutch 3 pressure tap (9). Connect one of the 8T-0855 Pressure Gauges to the fitting.

Test Procedure - Forward Clutch Pressure - Fifth Speed

1. Start the engine and set the throttle at low idle. Allow the machine to reach the proper operating temperature.

2. Turn on the autoshift function.

3. Shift the directional control lever to the FOURTH SPEED FORWARD position.

4. Increase the engine speed to high idle.

5. When the transmission output speed is approximately 1750 rpm. the solenoid for the forward high clutch and the solenoid for clutch 3 are energized.

   The pressure on the gauge for the forward high clutch (6) must be 1350 ± 250 kPa (195 ± 36 psi)

   The pressure on the gauge for the clutch 3 (9) must be 1500 ± 250 kPa (220 ± 36 psi)

6. When the test is complete, put the directional control in NEUTRAL, engage the parking brake, stop the engine and remove the test equipment.

Test Preparation - Reverse Clutch Pressure - First Speed

1. Install the 6V-3121 Multitach on the engine.

   ReferenceRefer to Special Instruction, SEHS7807, "Using The 6V2100 Multitach And 6V3121 Multitach Group" for detailed operating instructions for the Multitach.

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Illustration 18	g03257739
(2) Clutch one pressure tap (typical example) (3) Lubrication pressure tap (typical example) (4) Reverse clutch pressure tap (typical example)

2. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the reverse clutch pressure tap (4). Connect one of the 8T-0855 Pressure Gauges to the fitting.

3. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the clutch 1 pressure tap (2). Connect one of the 8T-0855 Pressure Gauges to the fitting.

Test Procedure - Reverse Clutch Pressure - First Speed

1. Start the engine and set the throttle at low idle. Allow the machine to reach the proper operating temperature.

2. Turn on the autoshift function.

3. With the transmission gear selector in the NEUTRAL position, shift the directional control lever to the FIRST SPEED REVERSE position.

4. Increase the engine speed to high idle.

   The pressure on the gauge for the reverse clutch (4) must be 1350 ± 250 kPa (195 ± 36 psi)

   The pressure on the gauge for the clutch 1 (2) must be 1500 ± 250 kPa (220 ± 36 psi)

5. When the test is complete, put the directional control in NEUTRAL, engage the parking brake, stop the engine and remove the test equipment.

Test Preparation - Reverse Clutch Pressure - Second Speed

1. Install the 6V-3121 Multitach on the engine.

   ReferenceRefer to Special Instruction, SEHS7807, "Using The 6V2100 Multitach And 6V3121 Multitach Group" for detailed operating instructions for the Multitach.

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Illustration 19	g03257739
(2) All wheel drive pressure tap (typical example) (3) Lubrication pressure tap (typical example) (4) Reverse clutch pressure tap (typical example)

2. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the reverse clutch pressure tap (4). Connect one of the 8T-0855 Pressure Gauges to the fitting.

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Illustration 20	g03250341
(8) Clutch number two pressure tap (typical example) (9) Clutch number three pressure tap (typical example)

3. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the clutch 2 pressure tap (8). Connect one of the 8T-0855 Pressure Gauges to the fitting.

Test Procedure - Reverse Clutch Pressure - Second Speed

1. Start the engine and set the throttle at low idle. Allow the machine to reach the proper operating temperature.

2. Turn on the autoshift function.

3. Shift the directional control lever to the SECOND SPEED REVERSE position.

4. Increase the engine speed to high idle.

5. When the transmission output speed is approximately 385 rpm. the solenoid for the reverse clutch and the solenoid for clutch 2 are energized.

   The pressure on the gauge for the reverse clutch (4) must be 1350 ± 250 kPa (195 ± 36 psi)

   The pressure on the gauge for the clutch 2 (8) must be 1500 ± 250 kPa (220 ± 36 psi)

6. When the test is complete, put the directional control in NEUTRAL, engage the parking brake, stop the engine and remove the test equipment.

Test Preparation - Reverse Clutch Pressure - Third Speed

1. Install the 6V-3121 Multitach on the engine.

   ReferenceRefer to Special Instruction, SEHS7807, "Using The 6V2100 Multitach And 6V3121 Multitach Group" for detailed operating instructions for the Multitach.

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Illustration 21	g03257739
(2) All wheel drive pressure tap (typical example) (3) Lubrication pressure tap (typical example) (4) Reverse clutch pressure tap (typical example)

2. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the reverse clutch pressure tap (4). Connect one of the 8T-0855 Pressure Gauges to the fitting.

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Illustration 22	g03250341
(8) Clutch number two pressure tap (typical example) (9) Clutch number three pressure tap (typical example)

3. Install a 6V-3965 Fitting and 3J-1907 O-Ring Seal into the clutch 3 pressure tap (9). Connect one of the 8T-0855 Pressure Gauges to the fitting.

Test Procedure - Forward Clutch Pressure - Third Speed

1. Start the engine and set the throttle at low idle. Allow the machine to reach the proper operating temperature.

2. Turn on the autoshift function.

3. Shift the directional control lever to the THIRD SPEED REVERSE position.

4. Increase the engine speed to high idle.

5. When the transmission output speed is approximately 840 rpm. the solenoid for the reverse clutch and the solenoid for clutch 3 are energized.

   The pressure on the gauge for the reverse clutch (4) must be 1350 ± 250 kPa (195 ± 36 psi)

   The pressure on the gauge for the clutch 3 (9) must be 1500 ± 250 kPa (220 ± 36 psi)

6. When the test is complete, put the directional control in NEUTRAL, engage the parking brake, stop the engine and remove the test equipment.

Test Preparation - Transmission Lubrication

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Illustration 23	g03257739
(2) All wheel drive pressure tap (typical example) (3) Lubrication pressure tap (typical example) (4) Reverse clutch pressure tap (typical example)

1. Connect one of the 8T-0855 Pressure Gauges to the lubrication pressure tap (3) .

Test Procedure - Transmission Lubrication

1. Start the engine and set the throttle at low idle. Allow the machine to reach the proper operating temperature.

2. Increase the engine speed to high idle.

3. The pressure on the gauge for the lubrication system (3) must be 25 to 300 kPa (4 to 44 psi)

4. When the test is complete, put the directional control in NEUTRAL, engage the parking brake, stop the engine and remove the test equipment.

Test Conclusions - Forward Clutch Pressure, Reverse Clutch Pressure, and Transmission Lubrication

Problem

Both forward clutch pressure and reverse clutch pressure is too low.

Probable Cause

• The spring in the regulator valve is weak.

• The oil level is low.

• The oil filter is plugged. Replace the dirty oil filter.

• Oil pump failure.

• The neutralizer button that is on the shift lever or the tilt control lever shorted. This condition caused the solenoid control valve to de-energize.

• The clutch piston seals are bad.

Problem

Either a forward clutch pressure or a reverse clutch pressure is too low.

Probable Cause

• The solenoid is faulty.

• The clutch piston seals are bad.

• The seals are faulty or the seals are missing on the input shaft.