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640 (Blue) (Key Power) CIRCUIT ISOLATED

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UTILIZE HYPERTEXT TO NAVIGATE TO COMPONENTS AND THEIR MACHINE LOCA- SYMBOLS AND DEFINITIONS PAGE
TION QUICKLY. HYPERTEXT IS INDICATED BY TEXT THAT IS BLUE AND UNDERLINED. ELECTRICAL SYMBOLS

Pressure Temperature Level

Switch Switch Switch Circuit Breaker

BASIC HYDRAULIC SYMBOLS

Fluid Pump Spring

Variability
Conditioner or Motor (Adjustable)

HOTKEYS (Keyboard Shortcuts)

FUNCTION KEYS
Zoom In “CTRL” / “+”
Zoom Out “CTRL” / “-”
Fit to Page “CTRL” / “0” (zero)
Hand Tool “SPACEBAR” (hold down)
Find “CTRL” / “F”
WHEN ONLY ONE CALLOUT IS SHOWING ON A Search “CTRL” / “SHIFT” / “F”

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BUTTON IS TYPICALLY LOCATED IN THE TOP RIGHT schematic locations. This document is best viewed at
CORNER OF EVERY MACHINE VIEW PAGE. a screen resolution of 1024 X 768.

© 2020 Caterpillar. All Rights Reserved. CAT, CATERPILLAR, LET’S DO THE

WORK, their respective logos, “Caterpillar Yellow,” the “Power Edge” and Cat
“Modern Hex” trade dress, as well as corporate and product identity used herein,
are trademarks of Caterpillar and may not be used without permission.
SCHEMATIC SYMBOLS AND DEFINITIONS
VALVES INTERNAL PASSAGEWAYS PUMPS BASIC HYDRAULIC
ENVELOPES FLOW IN ONE
DIRECTION
FLOW ALLOWED IN
EITHER DIRECTION
PARALLEL
FLOW
CROSS
FLOW
FIXED DISPLACEMENT
COMPONENT SYMBOLS

One Position Two Position Three Position Unidirectional Bidirectional Pump

Infinite Two Three Variability
Positioning Position Position or Motor
PORTS VARIABLE DISPLACEMENT
NON- COMPENSATED

CYLINDERS Fluid Spring

(Adjustable)
Two-way Three-Way Four-Way Conditioner
Unidirectional Bidirectional
CONTROL
AB
MOTORS
AB
Single Acting Double Acting
Pressure
FIXED DISPLACEMENT Spring
P T P T Compensation
Normal Position Shifted Position Infinite Position

CHECK
ACCUMULATORS Unidirectional Bidirectional Control Line Restriction
Valves (Variable)
VARIABLE DISPLACEMENT
Basic Spring Shuttle NON- COMPENSATED
Pilot
Symbol Loaded Line Restriction
Controlled Spring Loaded Gas Charged Restriction
(Fixed)

Unidirectional Bidirectional

PILOT CONTROL Line Restriction

MAIN AUX.

2-Section
ROTATING SHAFTS
RELEASED PRESSURE Variable and Pressure Pump
Compensated

External Return Internal Return Unidirectional Bidirectional

REMOTE SUPPLY PRESSURE Attachment Pump: Variable and
Pressure Compensated

Internal
Simplified Complete Supply Pressure Hydraulic Pneumatic
Energy Triangles

COMBINATION CONTROLS
LINES MEASUREMENT

Solenoid Solenoid Solenoid Solenoid and Servo Thermal Detent Crossing Joining
or Manual and Pilot Pilot or Manual Pressure Temperature Flow

MANUAL CONTROL FLUID STORAGE RESERVOIRS

Push-pull Lever Manual Shutoff General Manual Push Button Pedal Spring Vented Pressurized Return Above Fluid Level Return Below Fluid Level

HYDRAULIC SYMBOLS - ELECTRICAL ELECTRICAL SYMBOLS

G
M T

Pressure Temperature Level Flow

Transducer Transducer Generator Electric Pressure Pressure Switch Temperature Electrical
Switch Switch Switch Switch Circuit Breaker
(Fluid) (Gas / Air) Motor Switch (Adjustable) Switch Wire

BASIC ELECTRICAL COMPONENT SYMBOLS HARNESS AND WIRE SYMBOLS

Wire, Cable, or Harness Assembly Identification:
Fuse: A component in an electrical circuit that will open the circuit if too much current flows through it. Includes Harness Identification Letters and Harness
Connector Serialization Codes (see sample).
Switch (Normally Open): A switch that will close at a specified point (temp, press, etc.). The circle indicates
that the component has screw terminals and a wire can be disconnected from it.
AG-C4 L-C12
Switch (Normally Closed): A switch that will open at a specified point (temp, press, etc.). 111-7898 3E-5179
No circle indicates that the wire cannot be disconnected from the component. Part Number: for 1
Connector Plug
Ground (Wired): This indicates that the component is connected to a grounded wire. 2
The grounded wire is fastened to the machine.
Plug Receptacle
Pin or Socket Number
Ground (Case): This indicates that the component does not have a wire connected to ground.
It is grounded by being fastened to the machine. Harness Identification Letter(s): (A, B, C, AA, AB, AC, ...)
Harness Connector Serialization Code: The "C" stands for
"Connector" and the number indicates which connector in the
Reed Switch: A switch whose contacts are controlled by a magnet. A magnet closes the contacts of
harness (C1, C2, C3, ...)
a normally open reed switch; it opens the contacts of a normally closed reed switch.
L-C12
3E-5179
Sender: A component that is used with a temperature or pressure gauge.
The sender measures the temperature or pressure. 5A
T Its resistance changes to give an indication to the gauge of the temperature or pressure. Component
Fuse (5 Amps) 9X-1123 Part Number
Relay (Magnetic Switch): A relay is an electrical component that is activated by electricity. 325-AG135 PK-14
It has a coil that makes an electromagnet when current flows through it. Harness identification code:
This example indicates wire group 325, Wire Gauge*
The electromagnet can open or close the switch part of the relay. wire 135 in harness "AG". Wire Color
*Wire gauge is shown in AWG (American Wire Gauge)
Solenoid: A solenoid is an electrical component that is activated by electricity. but could also be shown in metric denoted with mm
It has a coil that makes an electromagnet when current flows through it.
The electromagnet can open or close a valve or move a piece of metal that can do work. 1 Deutsch connector: Typical representation
of a Deutsch connector. The plug contains all
2 sockets and the receptacle contains all pins.
Magnetic Latch Solenoid: An electrical component that is activated by electricity and held latched by a
permanent magnet. It has two coils (latch and unlatch) that make electromagnet 1 Sure-Seal connector: Typical representation
when current flows through them. It also has an internal switch that places of a Sure-Seal connector. The plug and receptacle
2 contain both pins and sockets.
the latch coil circuit open at the time the coil latches.

© 2020 Caterpillar. All Rights Reserved. CAT, CATERPILLAR, LET’S DO THE

WORK, their respective logos, “Caterpillar Yellow,” the “Power Edge” and Cat
“Modern Hex” trade dress, as well as corporate and product identity used herein,
are trademarks of Caterpillar and may not be used without permission.
 RENR8997-06
May 2020

938H and IT38H Wheel Loader

Hydraulic System
MCC1-UP
MJC1-UP
JKM1-UP
LKM1-UP
JNJ1-UP

© 2020 Caterpillar. All Rights Reserved. CAT, CATERPILLAR, LET’S DO THE WORK, their respective logos, “Caterpillar Yellow,” the “Power Edge”
and Cat “Modern Hex” trade dress, as well as corporate and product identity used herein, are trademarks of Caterpillar and may not be used without permission.
COMPONENT LOCATION
Part Machine Schematic
Description
Number Location Location
Implement System
Accumulator Gp - Pilot 275-7875 1 C-4, F-3
Accumulator. Gp - Ride Cntrl (Attch) 259-4685 2 D-1, F-1
Cylinder Gp - Lift 254-9037 3 C-3, F-2
Cylinder Gp - Tilt 346-1093
4 C-4, F-3
Tilt, High Lift 346-1094
Filter Gp - Pump Case Drain 285-2235 5 C-8
Manidfold Gp - Relief 277-9660 6 D-8
Plate - Orifice 317-5574 7 B-4, F-3
Pump Gp - Implement / Steering 304-9308 8 D-8
Screen 9T-9227 9 C-7
Tank Gp - Hydraulic Oil 255-2421 15 B-6, C-7
Valve - Breaker Relief, Vacuum 258-2829 16 C-8
Valve Gp - 2 Function 336-3818
2 Function w/ Ride Control (Attch) 336-3819
3 Function (Attch) 336-3820 17 B-2, E-1
3 Function w/ Ride Control (Attch) 336-3821
4 Function (Attch) 336-3822
Valve Gp - Ball, Dead Engine 112-1817 18 C-4, F-3
Valve Gp - Mntng, Power Control 286-8970 19 D-7
Valve Gp - Pilot, 2 Funct. (Attch), 1 Joystick 261-8653
Pilot, 2 Funct., 2 Levers 261-8654
Pilot, 3 Funct. (Attch), 1 Joystick 261-8655
20 F-5
Pilot, 3 Funct. (Attch), 3 Levers 261-8656
Pilot, 4 Funct. (Attch), 1 Joystick 261-8657
Pilot, 4 Funct. (Attch), 4 Levers 261-8658
Valve Gp - Ride Cntrl (Attach) 314-4008 21 C-1
Valve Gp - Tank Drain 245-5943 22 C-7
Steering System
Cylinder Gp - Steering 314-9340 23 F-8
Pump Gp - HMU 322-4638 24 F-8
Pump Gp - Sec. Steer (Attch) 313-5855 25 E-8
Screen Gp 306-4025 26 D-8
Valve Gp - Check 128-6847 27 E-8
Valve Gp - Check 303-5974 28 C-8
Valve Gp - Check, Sec. Steer (Attch) 9T-1013 29 E-8
Valve Gp - Priority, Steering 317-0953 30 D-8
Valve Gp - Shuttle, Load Sense 8J-6875 31 D-7
Fan / Brake System
Accumulator Gp - Brake (Charged) 279-0093 51 C-6
Cooler - Oil 282-2024 32 D-6
Control Gp - Foot Brake 271-0260 52 D-5
Filter Gp - Fan Return 330-9358 33 D-6
Manifold Gp - Brake / Fan 309-4907 34 C-6
Motor Gp - Fan 265-4925
35 D-6
Fan, Cold Start Attachment 330-0826
Pump Gp - Fan 254-5145 36 C-7
Sensor Gp - Position (Left Brake Pedal) 267-5222 53 D-5
Switch As - Limit (Stop Light) 105-6117 54 D-5
Valve Gp - Ball, Dead Engine 112-1817 37 C-6
Valve Gp - Brake Control (Service) 279-5719 55 C-5
Valve Gp - Check 175-0447 38 D-6
Valve Gp - Check, Cooler Bypass 145-8983 39 D-6
Valve Gp - Shutoff (Cold Start Attachment) 332-1166 40 D-7
Axle Hydraulic System (Attachment)
Accmltr. Gp - Diff. Lck. (Attch) 245-2975 41 B-7, F-7
Manifold Gp - Mntng, Man. Frnt Diff. Lck. 244-7139
42 B-7, F-7
Mntng, Auto. Frnt / Rear Diff. Lck. 244-7140
Pump Gp - Axle Oil Cooling (Attch) 273-1807 43 E-6
Screen Gp - Magnetic, Front Axle Cooling 251-6351 44 D-6
Screen Gp - Magnetic, Rear Axle Cooling 251-6351 45 E-6
Valve Gp - Relief,Axle Oil Clr Bypass 130-5202 46 E-6
Valve Gp - Shuttle, Diff. Lck 8J-6875 47 D-8
Quick Coupler (Attachment)
Cylinder Gp - Quick Coupler (Attch) 311-1463 48 A-3, D-3
Manifold Gp - Cntrl, Quick Coupler (Attch) 180-8585 49 A-4, D-3
Valve Gp - Ball, Dead Engine 112-1817 50 A-4, D-3
TAP LOCATION

Tap Schematic
Description
Number Location
G1 Fan Motor Supply Pressure D-7
G2 Fan Pump Load Sense Pressure C-7
G3 Implement / Steering Pump Load Sense D-8
G4 Implement / Steering Pump Discharge D-8
G5 Steering Supply Pressure D-8
G6 Schedule Oil Sampling (SOS) D-6
G7 Implement Pilot Supply Pressure F-3, C-4
G8 Brake Accumulator Pressure D-6
G9 Implement Supply Pressure E-3, B-4
G10 Fan / Brake Pump Discharge Pressure C-7
G11 Implmnt / Str Pump Case Drain Airbleed C-8
G12 Fan Motor Case Drain Airbleed D-6
G13 Differential Lock Pressure F-7
G14 Differential Lock Accumulator Pressure F-7
G15 Rear Brake Pressure C-5
G16 Front Brake Pressure C-5
 8 7 6 5 4 3 2 1

ENGINE END FRAME

(17) VALVE GP - 2ND FUNCTION
(3) CYLINDER GP 336-3818
LIFT 336-3819: 2ND FUNCTION W/ RIDE CONTROL (ATCH)
(20) VALVE GP (4) CYLINDER GP - TILT 254-9037 336-3820: 3RD FUNCTION (ATCH)
(23) CYLINDER GP PILOT 346-1093
REAR AXLE 336-3821: 3RD FUNCTION W/ RIDE CONTROL(ATCH)
STEERING STEERING
314-9340
261-8654: 2ND FUNCTION, 2 LEVERS
261-8653: 2ND FUNCTION (ATCH), 1 JOYSTICK
(1) ACCUMULATOR GP
PILOT
TILT, HIGH LIFT (ATCH): 346-1094 NOTE E
NOTE E
(2) ACCUMULATOR GP
261-8656: 3RD FUNCTION (ATCH), 3 LEVERS 275-7875
(41) ACCUMULATOR GP
DIFF. LOCK AXLE
261-8655: 3RD FUNCTION (ATCH), 1 JOYSTICK, 1 LEVER
(18) VALVE GP RAISE LIFT RIDE CONTROL (ATCH)
259-4685
261-8658: 4TH FUNCTION (ATCH), 4 LEVERS
RESERVOIR
(24) PUMP GP
(ATCH)
245-2975
DIFFERENTIAL
LOCK
261-8657: 4TH FUNCTION (ATCH), 1 JOYSTICK, 2 LEVER DEAD ENGINE
112-1817
RACK
F HMU
DIFFERENTIAL LOCK
NOTE E
NOTE F F
322-4638
PROPORTIONAL LEVER MOTION
L R SOLENOID G14 REAR DIFFERENTIAL
LOCK ON-OFF FORE AFT PILOT SHUT OFF
TILT LOWER
ROD END RIDE
CONTROL SOLENOID RIDE CONTROL
HEAD END RIDE
3RD FUNCTION
(ATTACHMENT)
A PR SOLENOID SOLENOID
DUMP (ATTACHMENT)
CONTROL SOLENOID

T A1 B1 a2 a3
a1 A2 B2 LOWER B3 A3
CO
G13 RH LH RH LH DUMP FLOAT
OPEN/RAISE
G7
DUMP RACK LOWER/ LIFT LIFT LIFT LIFT
RAISE ARM ARM
FLOAT ARM ARM C1
C2

(7) PLATE
ORIFICE
317-5574
4TH FUNCTION A PORT PILOT SEE 4TH FUNCTION WITH RIDE CONTROL
3RD FUNCTION A PORT PILOT
T
LOWER/FLOAT PILOT
a1 b1 a2 b2 a3 b3 a4 b4
DUMP PILOT
FLOAT
IMPLEMENT PILOT SUPPLY

T LS P
P C2 TC2 C1 TC1
IMPLEMENT RETURN
G9 DUMP LOWER
IMPLEMENT VALVE SUPPLY
FRONT DIFF. A T RH LIFT
(42) MANIFOLD GP LOCK ON-OFF IMPLEMENT LOAD SENSE HOLD
HOLD B
LS ARM
MOUNTING SOLENOID C1
VALVE DRAIN
AUTO FRONT / REAR DIFF. LOCK C0
(45) SCREEN GP RACK BACK PILOT P RACK
P
244-7140 HOLD
MANUAL FRONT DIFF. LOCK MAGNETIC BACK RAISE
RAISE PILOT
244-7139 251-6351 LH LIFT
E NOTE E NOTE E 3RD FUNCTION B PORT PILOT ARM
E
4TH FUNCTION B PORT PILOT SEE 4TH FUNCTION WITH RIDE CONTROL
(29) VALVE GP AXLE OIL COOLING RETURN
CHECK
M AXLE OIL COOLING SUCTION
SEC. STEER
(ATCH) QUICK COUPLER SUPPLY
4TH FUNCTION A PORT PILOT
9T-1013 (46) VALVE GP QUICK COUPLER RETURN
(43) PUMP GP LS OUT
RELIEF AXLE OIL 3RD FUNCTION A PORT PILOT NOTE A
(31) VALVE GP AXLE OIL COOLING FRONT DIFFERENTIAL LOCK
SHUTTLE (ATCH) COOLER BYPASS
LOWER/FLOAT PILOT
LOAD SENSE 273-1807 130-5202
8J-6875 NOTE C NOTE E DUMP PILOT
(27) VALVE GP
CHECK NOTE E 4TH FUNCTION B PORT PILOT
(25) PUMP GP 128-6847 DR
SEC. STEER
(ATCH)
G5 3RD FUNCTION B PORT PILOT
b1 RACK BACK b2 RAISE b3 CLOSE/LOWER
RAISE PILOT
313-5855
NOTE E RACK BACK PILOT

(26) SCREEN GP IMPLEMENT PILOT SUPPLY

306-4025 LS CF EF
IMPLEMENT RETURN (49) MANIFOLD GP
(19) VALVE GP CONTROL
IMPLEMENT VALVE SUPPLY QUICK COUPLER
(47) VALVE GP MOUNTING QUICK COUPLER (ATCH) (ATTACHMENT)
POWER CONTROL IMPLEMENT LOAD SENSE 180-8585
(30) VALVE GP SHUTTLE (35) MOTOR GP - FAN
POWER CONTROL NOTE E (48) CYLINDER GP
DIFF. LOCK 286-8970
PRIORITY, SOLENOID 265-4925 VALVE DRAIN QUICK COUPLER (ATCH)
STEERING 8J-6875 (ATCH FAN: 330-0826) QUICK COUPLER 311-1463
317-0953 NOTE E QUICK COUPLER RETURN SOLENOID NOTE E AXLE
(40) VALVE GP (50) VALVE GP RESERVOIR DIFFERENTIAL
G4 SHUT OFF
COLD START (ATCH) (32) COOLER
AXLE OIL COOLING RETURN DEAD ENGINE
112-1817
LOCK

D (6) MANIFOLD GP
G3 332-1166 (39) VALVE GP OIL
QUICK COUPLER SUPPLY
NOTE E
FRONT AXLE
D
RELIEF COOLER 282-2024 FRONT DIFFERENTIAL LOCK
277-9660 BYPASS
AXLE OIL COOLING SUCTION
145-8983
(53) SENSOR GP (54) SWITCH AS
POSITION
G12 (LEFT BRAKE PEDAL)
LIMIT

G6 (44) SCREEN GP (STOP LIGHT)

NON-ENGINE END FRAME - 2ND AND 3RD FUNCTION

MAGNETIC 267-5222 105-6117 (52) CONTROL GP
(38) VALVE GP 251-6351 FOOT BRAKE
(8) PUMP GP
IMPLEMENT/
G1 CHECK
175-0447 (51) ACCUMULATOR GP
NO
271-0260

STEERING VTL BRAKE

304-9308 (CHARGED)
NC
(2) ACCUMULATOR GP

G8
NOTE B 279-0093 C C
RIDE CONTROL (ATCH)
(33) FILTER GP 259-4685

LS
FAN RETURN
330-9358
G15 NOTE E
F PS PS1

HEAD END RIDE

CONTROL SOLENOID
(16) VALVE GP HEAD END RIDE
BRKR RELIEF FAN CONTROL CONTROL SOLENOID
VACUUM
G16
LS SOLENOID
258-2829 (5) FILTER GP
CASE DRAIN C1
(1) ACCUMULATOR GP (3) CYLINDER GP (21) VALVE GP
285-2235 A1 LIFT
(36) PUMP GP PILOT RIDE CONTROL (ATCH)
FAN
254-5145
(22) VALVE GP G10 G2 (55) VALVE GP 275-7875 (4) CYLINDER GP - TILT 254-9037 C2
314-4008

(28) VALVE GP
G11 NOTE B
TANK DRAIN
245-5943 P
BRAKE CONTROL
(SERVICE)
346-1093
TILT, HIGH LIFT (ATCH): 346-1094
NOTE E

C CHECK (15) TANK GP A2 279-5719 (18) VALVE GP NOTE E RAISE LIFT C

303-5974 HYDRAULIC OIL DEAD ENGINE
255-2421 112-1817
(34) MANIFOLD GP
CONTROL
NOTE F
RACK (17) VALVE GP
4 FUNCTION (ATCH)
(9) SCREEN GP
9T-9227 BRAKE / FAN TO SERVICE BRAKE 336-3822
309-4907 T TOP PORT (FRONT AXLE)
LOWER 3RD FUNCTION NOTE E
(Dimensions: 39 inches x 28 inches)

T1 (37) VALVE GP (ATTACHMENT)

DEAD ENGINE TO SERVICE BRAKE PILOT SHUT OFF
SOLENOID DUMP TILT 4TH FUNCTION
(REAR AXLE) (ATTACHMENT) RIDE CONTROL
112-1817
RENR8997-06

A1 B1 a1 A2 B2 a2 LOWER B3 A3 a3 B4 A4 a4 (ATTACHMENT)
DUMP OPEN/RAISE OPEN/RAISE

G7 FLOAT

NOTE A : RESOLVER OMITTED FROM LAST SECTION IN VALVE

STACK
NOTE B : FAN / IMPLEMENT / STEERING PUMP
DRIVE : ENGINE DRIVE RATIO = 1 : 1
FRONT AXLE (7) PLATE NOTE C : AXLE OIL COOLING PUMP
ORIFICE DRIVE : ENGINE DRIVE RATIO = 1.5748 : 1
317-5574
NOTE D : HIBERNATE ENGINE SPEED : 600 RPM
H H
LOW IDLE ENGINE SPEED : 800 RPM
T RATED ENGINE SPEED : 2100 RPM
HIGH IDLE ENGINE SPEED : 2340 RPM

4TH FUNCTION A PORT PILOT NOTE E : OPTIONAL ATTACHMENT

FLOAT
FROM STEERING/ 3RD FUNCTION A PORT PILOT NOTE F : DEAD ENGINE LOWER VALVE
IMPLEMENT PRIORITY VALVE
G9
30 Page,

LOWER/FLOAT PILOT DUMP LOWER

DUMP PILOT
T HYDRAULIC CIRCUIT COLOR DESCRIPTIONS
(41) ACCUMULATOR GP A RH LIFT RH LIFT
LS HOLD ARM ARM IMPLEMENT AND STEERING PUMP OUTPUT
DIFF. LOCK IMPLEMENT PILOT SUPPLY HOLD B C1 PILOT CIRCUIT
B (ATCH) IMPLEMENT RETURN
P
C0 FAN CONTROL CIRCUIT B
245-2975 P RACK HOLD HOLD SECONDARY STEERING PUMP OUTPUT
IMPLEMENT VALVE SUPPLY
BACK RAISE 4TH FUNCTION CONTROL CIRCUIT
IMPLEMENT LOAD SENSE LH LIFT LH LIFT SUPPLY LINE
C1 TC1 C2 TC2
P A PR
VALVE DRAIN
ARM ARM
DRAIN / RETURN LINE
BRAKE COOLING CIRCUIT
RACK BACK PILOT
STEERING CIRCUIT
RAISE PILOT COUPLER CYLINDERS AND CONTROL CIRCUIT
(15) TANK GP TILT CYLINDER CONTROL CIRCUIT
3RD FUNCTION B PORT PILOT
HYDRAULIC OIL 3RD FUNCTION CONTROL CIRCUIT
255-2421 4TH FUNCTION B PORT PILOT
LS OUT LIFT CYLINDERS AND RIDE CONTROL CIRCUIT
AXLE OIL COOLING RETURN DIFFERENTIAL LOCK CONTROL CIRCUIT
AXLE OIL COOLING SUCTION NOTE A IMPLEMENT AND FAN PUMP LOAD SENSE CIRCUIT

HYDRAULIC QUICK COUPLER SUPPLY

IMPLEMENT LOAD SENSE CIRCUIT

1
TANK QUICK COUPLER RETURN
FRONT DIFFERENTIAL LOCK LINE PATTERNS
DR
2 3
CO b1 RACK BACK b2 RAISE b3 CLOSE/LOWER b4 CLOSE/LOWER Pressure Line
T
Pilot / Load Sensing Pressure

Drain / Return Lines

Air Line
(42) MANIFOLD GP
MOUNTING Component Group
AUTO FRONT / REAR DIFF. LOCK QUICK COUPLER
QUICK COUPLER
H H 244-7140 SOLENOID (ATTACHMENT) CALLOUTS
MANUAL FRONT DIFF. LOCK
244-7139 (49) MANIFOLD GP YY Taps (Pressure, Sampling, Sensor - by letter)
A CONTROL AXLE Do not operate or work on this product unless you have
Connectors (By letter)
A
QUICK COUPLER (ATCH) RESERVOIR DIFFERENTIAL read and understood the instruction and warnings in the DL DL D
(50) VALVE GP LOCK relevant Operation and Maintenance Manuals and
180-8585 DEAD ENGINE relevant service literature. Failure to follow the instruc- Callout Number Component
NOTE E 112-1817 tions or heed the warnings could result in injury or (Machine Location from (52) VALVE GP - CONTROL Name

(48) CYLINDER GP FRONT AXLE death. Proper care is your responsibility.

Component LocationsTable)
138-1234
NOTE E
REAR AXLE
Part Number

QUICK COUPLER (ATCH)

311-1463 THIS SCHEMATIC IS FOR THE 938H AND IT38H WHEEL LOADER HYDRAULIC SYSTEM
NOTE E
MEDIA NUMBER: RENR8997-06
SCHEMATIC PART NUMBER (MAIN): 258-8893, CHANGE: 06, VERSION: -

DIFFERENTIAL LOCK CIRCUIT SCHEMATIC PART NUMBER (DIFFERENTIAL LOCK): 310-3567, CHANGE: 01, VERSION: -

NON-ENGINE END FRAME - 4TH FUNCTION WITH RIDE CONTROL ATCH

Components are shown installed on a fully operable machine with the key and engine off, transmission shifter
in neutral and with parking brake set.
Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations.
Refer to the Parts Manual using a specific serial number prefix in SIS before ordering parts from this schematic.

8 7 6 5 4 3 2 1
MACHINE COMPONENT LOCATIONS
VIEW ALL CALLOUTS

9 15 16 25 26 28 29 30 31 46 24 49 23 3 21 7 17 4

43

39
50
32
48
35
1
40
3
45

6
8 44 36 19 34 42 47 33 37 22 38 41 51 20 18 2
DIFFERENTIAL LOCK AND AXLE COOLING
COMPONENT LOCATIONS
VIEW ALL CALLOUTS

21

43

46

41
44
45

G14
42

G13
FAN / BRAKE COMPONENT LOCATIONS
VIEW ALL CALLOUTS

36

53 52
G6 G12 54
33

G2 38
39
37 G15
34

47
G8 40 G16
G10 55
35
G1
32

RIGHT SIDE, CENTER VIEW RIGHT SIDE, REAR VIEW LEFT PEDAL
IMPLEMENT COMPONENT LOCATIONS
VIEW ALL CALLOUTS

16
20 4 50
3
48
15
G11
9
17

5
49
1
G3
7
G14
G7
G4
6 G13 G9
18
19
22
RIGHT SIDE, CENTER VIEW RIGHT SIDE, FRONT
STEERING COMPONENT LOCATIONS
VIEW ALL CALLOUTS

24 27 29

28

30

26
23
25

31 G5