Bench Test Procedure For A 769C, 69D, 769D Off-Highway Truck, A 771C, 771D Quarry Truck, and A 768C Tractor Transmission{3030, 3073} Caterpillar

Off-Highway Truck/Tractor:

69D (S/N: 9SS1-UP; 9XS1-UP)

768C (S/N: 02X350-UP)

769C (S/N: 01X2877-UP)

769D (S/N: BBB1-UP; 5TR1-UP; 5SS1-UP)

Quarry Truck:

771C (S/N: 3BJ1-UP)

771D (S/N: BCA1-UP; 6JR1-UP; 6YS1-UP)

Introduction

Table 1

Revision	Summary of Changes in REHS3024
03	Updated High Idle Pressure section.
02	Updated Introduction. Added "Think Safety" graphic. Added Canceled Replaced Part Number statement. Updated Table 5.

© 2014 Caterpillar All Rights Reserved. This guideline is for the use of Cat dealers only. Unauthorized use of this document or the proprietary processes therein without permission may be violation of intellectual property law. Information contained in this document is considered Caterpillar: Confidential Yellow.

This special instruction contains the necessary information that is required to bench test-specific transmission arrangements. Refer to Table 2 for the correct arrangements. Bench testing the transmission ensures correct assembly and operation of the component. Rotating a transmission provides the most conclusive evaluation. This allows the dealer to ensure that the transmission will operate properly in the machine. The specifications in this guideline are specific to bench testing the component. Every effort has been made in order to provide the most current information that is known to Caterpillar. Continuing improvement and advancement of product design might have caused changes to your product which are not included in this publication. This guideline must be used with the latest technical information that is available from Caterpillar.

For questions or additional information concerning this guideline, submit a form for feedback in the Service Information System. In order to address an urgent issue, use the following resources in order to communicate your request to Caterpillar Repair Process Engineering:

• Caterpillar Dealer Technical Communicator

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Table 2

Machine Model	Transmission Arrangement
69D	145-7406
768C	7G-1140
769C	7G-1140
769D	7G-1140, 145-7406
771C	7G-1140
771D	7G-1140, 145-7406

Canceled Part Numbers and Replaced Part Numbers

This document may include canceled part numbers and replaced part numbers. Use NPR on SIS for information about canceled part numbers and replaced part numbers. NPR will provide the current part numbers for replaced parts.

Collecting the Test Data

Since conditions vary for each test bench, it is important to use the data that is collected from your test bench. The collected data is used to compare test results. The data should be collected and maintained by the operator.

Data from each transmission arrangement is collected and stored. Averages from each transmission arrangement are used in order to compare values on portions of this transmission test. Always compare data that is collected from the same transmission arrangement that is being tested. Averages for the last 20 transmission arrangements should be maintained.

Illustration 1	g02139237

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Personal injury or death can result from escaping fluid under pressure. Escaping fluid under pressure, even a very small pin-hole size leak, can penetrate body tissue and cause serious injury and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury. Always use a board or cardboard when checking for a leak.

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Hot oil and components can cause personal injury. Do not allow hot oil or components to contact skin.

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Personal injury or death can result from not following the proper procedures. To avoid the possibility of injury or death, follow the established procedure.

Tools Needed

Note: Pressures will be sensitive to tooling setup. The diameter of the hose, the diameter of a fitting, and additional filtering can affect pressure. The required tools that are listed in Table 3 were used in order to develop this test procedure.

Table 3

Required Tools
Tool	Part Number	Part Description	Qty
A	1U-9585	Block Gp (Transmission Mounting)	1
B	138-7575	Link Bracket	2
	0S-1589	Bolt (5/8-11X1.75 inch)	2
	5P-8247	Washer	2
C	1U-9722	Load Binder As (Ratchet Type)	3
D	4C-4627	Adapter Plate	1
	0S-1584	Bolt (1/2-20X1.75 inch)	4
	3B-4508	Lockwasher	4
E	136-3647	Drive Adapter	1
	0S-1588	Bolt (3/8-16X1.25 inch)	4
	5M-2894	Washer	4
F (1)	1U-9131	Drive Adapter (Key)	1
G	1U-8304	Fitting	1
	9U-7445	Adapter	1
	1P-4578	Half Flange	2
	8C-9024	Nipple (Plain)	1
	6V-3965	Nipple (Quick Disconnect)	1
	4J-0522	O-Ring Seal	1
	7M-8485	O-Ring Seal	1
	0T-0768	Bolt (7/16-14X1.75 inch)	4
	5P-8244	Washer	4
H	3B-6552	Elbow	1
	3B-7282	Nipple (Pipe)	1
	6V-4142	Nipple (Unvalved)	1
J	4C-4898	Test Cover	1
K (2)	1U-8304	Fitting	2
	9U-7446	Adapter	2
	1P-4579	Half Flange	4
	8C-9024	Nipple (Plain)	2
	6V-3965	Nipple (Quick Disconnect)	2
	4J-0524	O-Ring Seal	2
	7M-8485	O-Ring Seal	2
	1B-2886	Bolt (1/2-13X3.75 inch)	8
	5P-8245	Washer	8
L	6V-3966	Nipple (Quick Disconnect)	1
	8J-7844	Adapter Fitting	1
	3K-0360	O-Ring Seal	1
M	8C-9025	Coupler (Quick Disconnect)	1
	120-6843	Ball Valve	1
	8C-9024	Nipple (Plain)	1
N	9U-7500	Transmission Analyzer Tool Gp	1
	1U-9482	Adapter Cable As	1
	4C-5974	Cable Adapters	2
P	8T-0862	Pressure Gauge (-100 to 500 kPa (-15 to 72 psi))	1
	6V-4144	Coupler	1
R (3)	8T-0854	Pressure Gauge (0 to 1,000 kPa (0 to 145 psi))	7
	6V-4144	Coupler	7
S	8T-0855	Pressure Gauge (0 to 4,000 kPa (0 to 580 psi))	10
	6V-4144	Coupler	10

( 1 )	This drive adapter is used with the small drive shaft.
( 2 )	1U-5794 may be required in place of Tooling (K) .
( 3 )	This Tooling is used for the initial pressure checks.

Installation Procedure

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Illustration 2	g01219369

1. Install Tooling (A) on the rails of the test bench, as shown.

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Illustration 3	g01219401

2. Install Tooling (B) .

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Illustration 4	g01219387

3. Use a hoist to install the transmission on the test bench. The weight of the transmission is 1100 kg (2425 lb).

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Illustration 5	g01219404

4. Use Tooling (C) to secure the transmission to the test bench during testing.

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Illustration 6	g01219413

5. Install Tooling (D) .

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Illustration 7	g01219415

6. Install Tooling (E) to Tooling (D) .

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Illustration 8	g01219428

7. Install Tooling (F) to Tooling (E) .

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Illustration 9	g01219436

8. Connect the input drive shaft to Tooling (F) .

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Illustration 10	g01219442

9. Install the drive shaft guard.

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Illustration 11	g01219465

10. Remove bracket (1) .

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Illustration 12	g01626626

11. Install Tooling (G) .

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Illustration 13	g01219729

12. Remove oil drain plug (2) .

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Illustration 14	g01219741

13. Remove filter cover (3) .

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Illustration 15	g01219746
Typical Example

14. Remove the filter (4) from the filter assembly.

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Illustration 16	g01219749

15. Remove cover (5) .

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Illustration 17	g01219755

16. Remove plug (6) .

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Illustration 18	g01626717

17. Install Tooling (H) .

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Illustration 19	g01626719

18. Install Tooling (J) .

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Illustration 20	g01219797

19. Remove plug (7) .

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Illustration 21	g01092307

20. Install Tooling (K) .

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Illustration 22	g01219821

21. Install Tooling (L) .

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Illustration 23	g01626636

22. Install Tooling (M) to Tooling (K) .

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Illustration 24	g01219936
(8) Supply Oil

23. Connect hose assembly (8) from the pressurized flow meter to Tooling (H) .

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Illustration 25	g01626640
Control Valve Outlet

24. Connect hose assembly (9) from the Tooling (M) to the inlet of the No. 2 flow meter.

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Illustration 26	g01626646

25. Connect hose assembly (10) from the outlet of the No. 2 flow meter to Tooling (K) .

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Illustration 27	g01626650
Transmission Lubrication Oil

Note: If you are using individual pressure gauges to measure the pressures, refer to Table 3 for the correct pressure gauges.

26. Connect a pressure line (11) to the lubrication pressure tap.

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Illustration 28	g01626661
Control Valve Outlet

27. Connect a pressure line to pressure tap (12) .

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Illustration 29	g01220055
(13) Pump Pressure

28. Connect a pressure line (13) to Tooling (L) .

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Illustration 30	g01220058
(14) Priority Reducing Valve Pressure

29. Connect a pressure line (14) to Tooling (H) .

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Illustration 31	g01220067
(15) Pressure tap "A" for the No. 2 clutch (16) Pressure tap "B" for the No. 1 clutch (17) Pressure tap "C" for the No. 7 clutch (18) Pressure tap "E" for the No. 5 clutch (19) Pressure tap "F" for the No. 4 clutch (20) Pressure tap "G" for the No. 6 clutch (21) Pressure tap "H" for the No. 3 clutch

30. Connect pressure lines (15), (16), (17), (18), (19), (20), and (21) to pressure taps.

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Illustration 32	g01220072
(22) Upshift Solenoid

31. Connect Tooling (N) to the upshift solenoid (22) .

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Illustration 33	g01220085

32. Connect Tooling (N) to the downshift solenoid (23) .

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Illustration 34	g01220099

33. Connect Tooling (N) to the transmission, as shown.

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Illustration 35	g01220104

34. Connect Tooling (N) to a suitable location, as shown.

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Illustration 36	g01220126
Transmission Analyzer II

35. Connect Tooling (N) to a power source. Refer to Tool Operating Manual, NEHS0644 for the correct operating instructions.

Test Procedure

Harness Test

1. Make sure that the harness is properly connected.

2. Use Tooling (N) to perform the harness test.

3. Record the values in Table 8.

Start Checks

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Personal injury or death can result from not following the proper procedures. To avoid the possibility of injury or death, follow the established procedure.

Note: Refer to Testing and Adjusting, SENR6869, "768C Tractor and 769C Truck Power Train", Testing and Adjusting, SENR6887, "771C Quarry Truck Power Train", or Testing and Adjusting, SENR8611-01, "769D Truck and 771D Quarry Truck Power Train " for the correct adjusting procedures.

1. The preferred oil is SAE 10W oil viscosity grade. Warm oil to 50 °C (125 °F). If you are using Mobil DTE11 oil, warm the oil to 34 °C (95 °F). Maintain this temperature for the duration of the test.

2. Adjust the input flow to 57 ± 4 L/min (15 ± 1 US gpm).

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Illustration 37	g02720621

3. With the transmission in the NEUTRAL position, rotate the input shaft in a counterclockwise direction. Adjust the input rotation to 650 ± 30 rpm.

4. Shift the transmission through all speed ranges in order to eliminate air from the transmission controls.

5. Check for lockup or excessive drag in all ranges.

6. Stop the input rotation.

7. Stop the input flow.

Priority Reducing Valve

1. Adjust the input flow to 57 ± 4 L (15 ± 1 US gal).

2. Adjust the input rotation to 650 ± 30 rpm in the NEUTRAL position.

3. Shift the transmission to the FORWARD 1 position.

4. The priority reducing valve pressure must be 1725 ± 70 kPa (250 ± 10 psi).

5. Record the value in Table 9.

Neutralizer Valve

1. Stop the input flow and the input rotation in a range that is not NEUTRAL.

2. Adjust the input flow to 57 ± 4 L/min (15 ± 1 US gpm).

3. Adjust the input rotation to 650 ± 30 rpm.

4. The neutralizer valve must prevent a pressure increase at any clutch station.

5. Record the values in Table 10.

6. Shift the transmission to the NEUTRAL position. The clutch pressure that is measured at pressure tap "B" must rise to a normal pressure.

7. Record the value in Table 11.

Lubrication Relief Valve

1. With the transmission in FIRST, adjust the input flow in order to produce a lubrication outlet flow of 38 ± 0.4 L/min (10 ± 0.1 US gpm).

2. Use Tooling (M) in order to momentarily block the flow at the torque converter inlet.

3. The lubrication outlet pressure must be 930 ± 100 kPa (135 ± 15 psi).

4. Record the value in Table 12.

5. Open Tooling (M) .

Lubrication Check

1. Adjust the input flow to 57 ± 4 L/min (15 ± 1 US gpm).

2. Adjust the input rotation to 650 ± 30 rpm.

3. With the transmission in the REVERSE and FORWARD 1, the lubrication pressure must be 26.2 ± 6.2 kPa (3.8 ± 0.9 psi) and the lubrication flow must be 50.7 ± 5.7 L/min (13.4 ± 1.5 US gpm).

4. Record the values in Table 13.

5. Adjust the input flow to 170 ± 4 L/min (45 ± 1 US gpm).

6. Adjust the input rotation to 2150 ± 30 rpm.

7. In all FORWARD and REVERSE ranges, the lubrication pressure must be 200 ± 7 kPa (29 ± 1 psi) and the lubrication flow must be 161 ± 5.7 L/min (42.5 ± 1.5 US gpm).

8. Record the values in Table 14.

Lubrication Circuit Check

1. Shift the transmission to FORWARD 2.

2. Adjust the input flow until the lubrication flow is 132.5 ± 0.4 L/min (35 ± 0.1 US gpm). Maintain this flow during this check.

3. Adjust the input rotation to 2150 ± 30 rpm.

4. The lubrication pressure must be 143 ± 11 kPa (20.8 ± 1.6 psi).

5. Record the value in Table 15.

Primary Clutch Pressures

1. Remove Tooling (J) .

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Illustration 38	g01630093

2. Remove the load piston plugs (24) from selector valve "A", "B", "C", "E", "F", "G"and "H".

3. Install Tooling (J) .

4. Adjust the input flow to 57 ± 4 L/min (15 ± 1 US gpm).

5. Adjust the input rotation to 650 ± 30 rpm.

6. Shift the transmission through each gear range.

   Note: Do not shift the transmission into REVERSE with the input rpm higher than 650 rpm.

7. Record the primary clutch pressure for each gear range in Table 16.

8. Record the pump pressure in Table 16.

9. Verify that the pump and primary clutch pressures match the values in Table 4.

10. Shift the transmission to the NEUTRAL position.

Table 4

Initial Pressure Check
Gear Range	Engaged Clutches	Pump Pressure	Station (1) (2)
			"A"	"B"	"C"	"E"	"F"	"G"	"H"
			Pressure (3)	Pressure (3)	Pressure (3)	Pressure (3)	Pressure (3)	Pressure (3)	Pressure (3)
R	3 and 7	2515 kPa (365 psi) Min	520 kPa (75 psi)	-	-	-	-	-	345 kPa (50 psi)
N	1		-	345 kPa (50 psi)	-	-	-	-	-
1F	2 and 6		-	-	380 kPa (55 psi)	-	-	345 kPa (50 psi)	-
2F	1 and 6		-	345 kPa (50 psi)	-	-	-	345 kPa (50 psi)	-
3F	3 and 6		520 kPa (75 psi)	-	-	-	-	345 kPa (50 psi)	-
4F	1 and 5		-	345 kPa (50 psi)	-	380 kPa (55 psi)	-	-	-
5F	3 and 5		520 kPa (75 psi)	-	-	380 kPa (55 psi)	-	-	-
6F	1 and 4		-	345 kPa (50 psi)	-	-	380 kPa (55 psi)	-	-
7F	3 and 4		520 kPa (75 psi)	-	-	-	380 kPa (55 psi)	-	-

( 1 )	Station "D" is not used.
( 2 )	Refer to the Testing and Adjusting, "Transmission Hydraulic Control (Pressure Pack) - Test and Adjust" for the proper procedure to adjust the stations.
( 3 )	The tolerance is + 50 − 35 kPa (+ 7 − 5 psi).

Low Idle Pressure

1. Adjust the input flow to 57 ± 4 L/min (15 ± 1 US gpm).

2. Adjust the input rotation to 650 ± 30 rpm with the transmission in the NEUTRAL position.

3. Shift the transmission through each gear range.

   Note: Do not shift the transmission into REVERSE with the input rpm higher than 650 rpm.

4. Record the clutch pressures in Table 17.

5. Record the pump pressure in Table 17.

   Note: Pump pressure should be a minimum of 2516 kPa (365 psi).

6. Verify that the pump and clutch pressures match the values in Table 5.

7. Shift the transmission to the NEUTRAL position.

8. Stop the input rotation.

Table 5

Clutch Pressures At Low Idle
Gear Range	Engaged Clutches 4	Station (1) (2)
		"A"	"B"	"C"	"E"	"F"	"G"	"H"
		Pressure (3)	Pressure (3)	Pressure (3)	Pressure (3)	Pressure (3)	Pressure (3)	Pressure (3)
R	3 and 7	1700 kPa (247 psi)	-	-	-	-	-	2760 kPa (400 psi)
N	1	-	2035 kPa (295 psi)	-	-	-	-	-
1F	2 and 6	-	-	1885 kPa (273 psi)	-	-	2760 kPa (400 psi)	-

( 1 )	Station "D" is not used.
( 2 )	Refer to the Power Train Testing and Adjusting, "Transmission Hydraulic Control (Pressure Pack) - Test and Adjust" for the proper procedure to adjust the Stations.
( 3 )	The tolerance is + 240 − 100 kPa (+ 35 − 15 psi).

High Idle Pressure

1. Adjust the input flow to 170 ± 4 L/min (45 ± 1 US gpm).

2. Adjust the input rotation to 600 rpm.

3. Shift the transmission into FORWARD 1 position.

4. Adjust the input rotation to 2150 ± 30 rpm .

5. Record the clutch pressures in Table 18.

6. Record the pump pressure in Table 18.

   Note: Pump pressure should be a maximum of 3275 kPa (475 psi).

7. Verify that the pump and clutch pressures match the values in Table 6.

8. Repeat steps 2 through 7 for all gear ranges.

9. Shift the transmission to the NEUTRAL position.

10. Stop the input rotation.

Table 6

Clutch Pressures At High Idle
Gear Range	Engaged Clutches	Station (1) (2)
		"A"	"B"	"C"	"E"	"F"	"G"	"H"
		Pressure (3)	Pressure (3)	Pressure (3)	Pressure (3)	Pressure (3)	Pressure (4)	Pressure (4)
R	3 and 7	1700 kPa (247 psi)	-	-	-	-	-	2930 kPa (425 psi)
N	1	-	2035 kPa (295 psi)	-	-	-	-	-
1F	2 and 6	-	-	1885 kPa (273 psi)	-	-	2930 kPa (425 psi)	-
2F	1 and 6	-	2035 kPa (295 psi)	-	-	-	2930 kPa (425 psi)	-
3F	3 and 6	1700 kPa (247 psi)	-	-	-	-	2930 kPa (425 psi)	-
4F	1 and 5	-	2035 kPa (295 psi)	-	2015 kPa (292 psi)	-	-	-
5F	3 and 5	1700 kPa (247 psi)	-	-	2015 kPa (292 psi)	-	-	-
6F	1 and 4	-	2035 kPa (295 psi)	-	-	1430 kPa (207 psi)	-	-
7F	3 and 4	1700 kPa (247 psi)	-	-	-	1430 kPa (207 psi)	-	-

( 1 )	Station "D" is not used.
( 2 )	Refer to the Testing and Adjusting, "Transmission Hydraulic Control (Pressure Pack) - Test and Adjust" for the proper procedure to adjust the stations.
( 3 )	The tolerance is + 240 − 100 kPa (+ 35 − 15 psi).
( 4 )	The tolerance is ± 280 kPa ( ± 41 psi).

Contamination Control

1. Take an oil sample of the test bench oil supply. Oil contamination must be maximum ISO 16/13.

2. Record the results in Table 19.

3. Remove the transmission from the test bench if the test bench oil supply is within specifications.

Transmission Bench Test Data Sheet

Table 7

CATERPILLAR	Transmission Bench Test Data Sheet	Test Date:
		Model: 69D, 768C, 769C, 769D, 771C, 771D
Work Order:		Serial No.:

Harness Test

Table 8

Harness Test	Upshift Solenoid	Downshift Solenoid
	_______ Ω	_______ Ω

Priority Reducing Valve

Table 9

Priority Reducing Valve Pressure

Input Speed (650 ± 30 rpm) in NEUTRAL Input Flow 57 ± 4 L/min (15 ± 1 US gpm) Gear Range FORWARD 1

kPa (psi)

Neutralizer Valve

Table 10

Neutralizer Valve (Step 1)			Input Speed (650 ± 30 rpm) Input Flow 57 ± 4 L/min (15 ± 1 US gpm) Any Gear Range Except NEUTRAL
A	B	C	D	E	F	G	H
kPa (psi)	kPa (psi)	kPa (psi)	kPa (psi)	kPa (psi)	kPa (psi)	kPa (psi)	kPa (psi)

Table 11

Neutralizer Valve (Step 2)		Gear Range NEUTRAL
Station "B"		kPa (psi)	The clutch pressure must rise to normal pressure.		Yes	No

Lubrication Relief Valve Check

Table 12

Lubrication Outlet Pressure

Input Speed (650 ± 30 rpm) Restricted Lubrication Outlet Flow

kPa (psi)

Lubrication Check

Table 13

Lubrication Check	Input Speed (650 ± 30 rpm) Input Flow 57 ± 4 L/min (15 ± 1 US gpm)
Gear Range	Lubrication Pressure		Lubrication Flow
R	kPa (psi)		kPa (psi)
1F	kPa (psi)		kPa (psi)

Table 14

Lubrication Check	Input Speed (2150 ± 30 rpm) Input Flow 170 ± 4 L/min (45 ± 1 US gpm)
Gear Range	Lubrication Pressure		Lubrication Flow
R	kPa (psi)		kPa (psi)
1F	kPa (psi)		kPa (psi)
2F	kPa (psi)		kPa (psi)
3F	kPa (psi)		kPa (psi)
4F	kPa (psi)		kPa (psi)
5F	kPa (psi)		kPa (psi)
6F	kPa (psi)		kPa (psi)
7F	kPa (psi)		kPa (psi)

Lubrication Circuit Check

Table 15

Lubrication Pressure

Gear Range FORWARD 2 Input Speed (2150 ± 30 rpm) Outlet Flow 132.5 ± 0.4 L/min (35 ± 0.1 US gpm)

kPa (psi)

Primary Clutch Pressure Checks

Table 16

Initial Pressure Check
Gear Range	Engaged Clutches	Pump Pressure	Station
			"A"	"B"	"C"	"E"	"F"	"G"	"H"
			Pressure	Pressure	Pressure	Pressure	Pressure	Pressure	Pressure
R	3 and 7
N	1
1F	2 and 6
2F	1 and 6
3F	3 and 6
4F	1 and 5
5F	3 and 5
6F	1 and 4
7F	3 and 4

Low Idle Pressure Check

Table 17

Clutch Pressures At Low Idle
Gear Range	Engaged Clutches 4	Pump Pressure	Station
			"A"	"B"	"C"	"E"	"F"	"G"	"H"
			Pressure	Pressure	Pressure	Pressure	Pressure	Pressure	Pressure
R	3 and 7
N	1
1F	2 and 6

High Idle Pressure Check

Table 18

Clutch Pressures At High Idle
Gear Range	Engaged Clutches	Pump Pressure	Station
			"A"	"B"	"C"	"E"	"F"	"G"	"H"
			Pressure	Pressure	Pressure	Pressure	Pressure	Pressure	Pressure
R	3 and 7
N	1
1F	2 and 6
2F	1 and 6
3F	3 and 6
4F	1 and 5
5F	3 and 5
6F	1 and 4
7F	3 and 4

Contamination Control

Table 19

ISO Particle Count

Sample the test bench oil supply.

________/________Particle Count

Table 20

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