Procedure to Improve the Cross Support for the Exhaust Tubes on Certain 797F Off-Highway Trucks{0635, 1061} Caterpillar

Off-Highway Truck:

797F (S/N: LAJ1-587; WSP1-129)

Introduction

The following procedure includes the required parts and information to improve the cross support for the exhaust tubes on certain 797F Off-Highway Trucks.

Refer to the appropriate section:

• For a 797F Standard Configuration, refer to ""797F Standard Configuration Rework Instructions" "

• For a 797F High Altitude Arrangement (HAA) Configuration, refer to ""797F High Altitude Arrangement Configuration Rework Instructions" "

• For a 797F XQ Configuration, refer to ""797F XQ Configuration Rework Instructions" "

Important Safety Information

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Do not operate or work on this machine unless you have read and understand the instructions and warnings in the Operation and Maintenance Manuals. Failure to follow the instructions or heed the warnings could result in injury or death. Contact your Cat dealer for replacement manuals. Proper care is your responsibility.

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Accidental engine starting can cause injury or death to personnel working on the equipment. To avoid accidental engine starting, disconnect the battery cable from the negative (−) battery terminal. Completely tape all metal surfaces of the disconnected battery cable end in order to prevent contact with other metal surfaces which could activate the engine electrical system. Place a Do Not Operate tag at the Start/Stop switch location to inform personnel that the equipment is being worked on.

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Personal injury or death can result from improper lifting or blocking. When a hoist or jack is used to lift any part or component, stand clear of the area. Be sure the hoist or jack has the correct capacity to lift a component. Install blocks or stands before performance of any work under a heavy component. Approximate weights of the components are shown. Clean all surfaces where parts are to be installed.

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Falling Hazard. May cause personal injury or death. Always attach safety lanyard to appropriate fixing point.

Machine Preparation

1. Move the machine to a hard level surface.

2. Avoid sudden steering inputs when you are parking the machine.

3. Apply the service brakes in order to stop the machine.

4. Move the transmission control lever to the PARK position.

5. Turn the engine start switch to the OFF position in order to stop the engine.

6. Turn the battery disconnect switch to the OFF position.

7. Disconnect the battery. Refer to Operation and Maintenance Manual, "Battery or Battery Cable - Inspect/Replace" for additional information disconnecting the battery.

8. Chock the front wheels and the rear wheels. Refer to Disassembly and Assembly, "Wheel Chock (Front and Rear) - Remove and Install".

9. Release the pressure from the system. Refer to Operations and Maintenance Manual, "System Pressure Release".

797F Standard Configuration Rework Instructions

Removal Procedure

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Illustration 1	g03844904
(A) Tube assembly (B) Tube assembly

1. Remove and retain tube assembly (A) and tube assembly (B). Retain all mounting hardware.

   Note: Refer to Disassembly and Assembly, KENR8384, "Engine and Torque Converter - Remove and Install" for specific removal information.

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Illustration 2	g03845023
(C) Bracket assembly (D) Bracket assembly (E) Bracket assembly

2. Remove bracket assemblies (D) and bracket assemblies (E) from bracket assembly (C). Discard bracket assemblies (D), and retain bracket assemblies (E) and all mounting hardware.

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Illustration 3	g03848570
(C) Bracket assembly (F) Hose assembly (if equipped) (G) Harness assembly (H) Clip (if quipped) (J) Clipping

3. If equipped, remove and discard clips (H) that secure hose assembly (F) .

   Note: Hose assembly (F) is for the Oil Renewal System (ORS) and may not be equipped on your machine.

4. Remove and discard clipping (J) for harness assembly (G) .

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Illustration 4	g03848737
(C) Bracket assembly

5. Remove and discard bracket assembly (C) and all mounting hardware.

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Illustration 5	g03844979
(K) Hose assembly (L) Clipping (M) Bolt (N) Washer (P) Spacer (R) Clipping (S) Bolt (T) Washer (U) Spacer (V) Hose assembly (W) Bolt (X) Washer (Y) Clipping (Z) Clipping (AA) Stud (AB) Spacer (AC) Nut (AD) Washer

6. Remove clipping (L) and clipping (R) that secure hose assembly (K). Retain clipping (L), clipping (R), bolt (S), washer (T), and spacer (U). Discard bolt (M), washer (N), and spacer (P) .

7. Remove clipping (Y) and clipping (Z) that secure hose assembly (V). Retain clipping (Y), clipping (Z), bolt (W), washer (X), nut (AC), and washer (AD). Discard stud (AA) and spacer (AB) .

Fabrication Procedure

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Illustration 6	g03844906
(AE) Boss (AF) Boss (AG) Boss

1. Remove boss (AE), boss (AE), and boss (AG) from the frame.

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Illustration 7	g03844980
(1) 7Y-6338 Boss

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Illustration 8	g03845481
(1) 7Y-6338 Boss (AH) 130.2 mm (5.12 inch) (AJ) 291.5 mm (11.47 inch)

Note: Refer to Special Instruction, REHS1841, "General Welding Procedures" prior to performing any welding on the machine.

2. Prepare the area on the frame for welding. Remove all paint, dirt, oil, or debris from the area. Remove, relocate, or protect any components that may become damaged from nearby welding.

   Weld boss (1) to the frame.

   Repaint the welded area, as needed.

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Illustration 9	g03848820
(1) 7Y-6338 Boss (2) 178-7023 Boss

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Illustration 10	g03848845
(1) 7Y-6338 Boss (2) 178-7023 Boss (AK) 150 mm (5.90 inch) (AL) 100 mm (3.93 inch) (AM) 150 mm (5.90 inch) (AN) 50 mm (1.96 inch)

Note: Refer to Special Instruction, REHS1841, "General Welding Procedures" prior to performing any welding on the machine.

3. Prepare the area on the frame for welding. Remove all paint, dirt, oil, or debris from the area. Remove, relocate, or protect any components that may become damaged from nearby welding.

   Weld boss (1) and boss (2) to the frame.

   Repaint the welded area, as needed.

Installation Procedure

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Illustration 11	g03845441
(3) 125-8534 Plate As (4) 288-7158 Stud

1. Secure plate assembly (3) to the existing stud from the wiring group by using the existing nut and washer.

   Secure stud (4) to the existing boss on the frame.

   Note: Tighten stud (4) to 35 ± 5 N·m (26 ± 3.6 lb ft).

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Illustration 12	g03845578
(1) 7Y-6338 Boss (3) 125-8534 Plate As (4) 288-7158 Stud (5) 8T-4172 Bolt (6) 8T-4121 Hard Washer (7) 138-7500 Spacer (8) 136-4992 Spacer (K) Hose assembly (L) Clipping (R) Clipping (S) Bolt (T) Washer (U) Spacer (V) Hose assembly (W) Bolt (X) Washer (Y) Clipping (Z) Clipping (AC) Nut (AD) Washer

2. Secure hose assembly (K) to the top boss on the frame by using retained clipping (L), bolt (5), hard washer (6), and spacer (7) .

   Secure hose assembly (K) to plate assembly (3) by using retained clipping (R), bolt (S), washer (T), and spacer (U) .

3. Secure hose assembly (V) and the existing clipping from the chassis harness assembly to stud (4) by using spacer (8), retained clipping (Z), nut (AC), and washer (AD) .

   Secure hose assembly (V) to boss (1) by using retained clipping (Y), bolt (W), and washer (X) .

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Illustration 13	g03848971
(1) 7Y-6338 Boss (2) 178-7023 Boss (6) 8T-4121 Hard Washer (9) 5P-7468 Clip (10) 5P-7469 Clip (11) 5P-8444 Grommet (12) 8T-4136 Bolt (13) 204-2281 Cable Strap (G) Harness assembly (AP) Cable assembly

4. Secure harness assembly (G) to boss (1) and boss (2) by using two clips (9), two clips (10), two grommets (11), two bolts (12), and two hard washers (6) .

   Secure existing cable assembly (AP) to harness assembly (G) by using five cable straps (13) .

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Illustration 14	g03849101
(F) Hose assembly (if equipped) (6) 8T-4121 Hard Washer (12) 8T-4136 Bolt (14) 287-0310 Spacer (15) 350-1571 Bracket As (16) 7X-2543 Bolt (17) 7D-7233 Clip

5. If equipped, secure hose assembly (F) to the existing clipping locations by using two clips (17), bolt (16), bracket assembly (15), spacer (14), two bolts (12), and three hard washers (6) .

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Illustration 15	g03845127
(18) 459-4023 Bracket (19) 8T-4184 Bolt (20) 198-4778 Hard Washer

6. Secure bracket (18) to the frame by using four bolts (19) and four hard washers (20) .

   Note: Do not final tighten bolts until all the exhaust components have been connected and adjusted properly.

   Note: After all the exhaust components have been installed, final tighten bolts (19) to 105 ± 20 N·m (77 ± 15 lb ft).

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Illustration 16	g03845138
(18) 459-4023 Bracket (21) 465-8067 Bracket As (22) 465-8062 Bracket As (23) 8T-4956 Bolt (24) 5P-1076 Hard Washer

7. Secure bracket assembly (21) and bracket assembly (22) to bracket (18) by using four bolts (23) and four hard washers (24) .

   Note: Do not final tighten bolts until all the exhaust components have been connected and adjusted properly.

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Illustration 17	g03845599
(21) 465-8067 Bracket As (22) 465-8062 Bracket As (E) Bracket assembly

8. Secure retained bracket assemblies (E) to bracket assembly (21) and bracket assembly (22) by using the retained hardware.

   Note: Do not final tighten bolts until all the exhaust components have been connected and adjusted properly.

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Illustration 18	g03846344
(A) Tube assembly (B) Tube assembly

9. Reinstall tube assembly (A) and tube assembly (B) and any other removed exhaust components by using the retained hardware.

   Note: Refer to Disassembly and Assembly, KENR8384, "Engine and Torque Converter - Remove and Install" for specific installation information.

   Note: After all the exhaust components have been connected and adjusted properly, final tighten all bolts.

797F High Altitude Arrangement Configuration Rework Instructions

Prior to performing the following rework instructions, ensure that the exhaust has already been updated according to Special Instruction, REHS8638, "Procedure to Retrofit the Exhaust Group on the High Altitude Engine for the 797F Off-Highway Truck".

Removal Procedure

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Illustration 19	g03845516
(A) Tube assembly (B) Tube assembly

1. Remove and retain tube assembly (A) and tube assembly (B). Retain all mounting hardware.

   Note: Refer to Disassembly and Assembly, KENR8384, "Engine and Torque Converter - Remove and Install - High Altitude" for specific removal information.

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Illustration 20	g03847490
(C) Bracket assembly

2. Remove and retain bracket assemblies (C). Retain all mounting hardware.

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Illustration 21	g03847491
(D) Harness assembly (E) Clipping (F) Hose assembly (if equipped) (G) Clip (if equipped)

3. If equipped, remove and discard clips (G) that secure hose assembly (F) .

   Note: Hose assembly (F) is for the Oil Renewal System (ORS) and may not be equipped on your machine.

4. Remove and discard clipping (E) that secures harness assembly (D) .

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Illustration 22	g03847492
(H) Bracket assembly (J) Bracket assembly (K) Bracket assembly

5. Remove and discard bracket assembly (H), bracket assembly (J), bracket assembly (K), and all associated mounting hardware.

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Illustration 23	g03850440
(L) Hose assembly (M) Clipping (N) Bolt (P) Washer (R) Spacer (S) Clipping (T) Bolt (U) Washer (V) Spacer (W) Hose assembly (X) Bolt (Y) Washer (Z) Clip (AA) Clip (AB) Hose assembly (AC) Bolt (AD) Washer (AE) Clipping (AF) Clipping (AG) Stud (AH) Spacer (AJ) Nut (AK) Washer

6. Remove clipping (M) and clipping (S) that secures hose assembly (L). Retain clipping (M), clipping (S), bolt (T), washer (U), and spacer (V). Discard bolt (N), washer (P), and spacer (R) .

7. Remove clip (Z) and clip (AA) that secures hose assembly (W). Retain clip (AA), bolt (X), and washer (Y). Discard clip (Z) .

8. Remove clipping (AE) and clipping (AF) that secure hose assembly (AB). Retain clipping (AE), clipping (AF), bolt (AC), washer (AD), nut (AJ), and washer (AK). Discard stud (AG), and spacer (AH) .

Fabrication Procedure

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Illustration 24	g03850610
(AL) Boss (AM) Boss (AN) Boss

1. Remove boss (AL), boss (AM), and boss (AN) from the frame.

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Illustration 25	g03850618
(1) 7Y-6338 Boss (2) 441-1422 Block (3) 178-7023 Boss

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Illustration 26	g03850619
View of the inside right-hand frame (1) 7Y-6338 Boss (2) 441-1422 Block (AP) 291.5 mm (11.47 inch) (AR) 482.6 mm (19.00 inch) (for reference only) (AS) 130.2 mm (5.12 inch) (AT) 51.9 mm (2.04 inch)

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Illustration 27	g03850763
View of the inside rear of the frame (1) 7Y-6338 Boss (2) 441-1422 Block (3) 178-7023 Boss (AU) 100 mm (3.93 inch) (AV) 150 mm (5.90 inch) (AW) 50 mm (1.96 inch) (AX) 150 mm (5.90 inch) (AY) 385.4 mm (15.17 inch) (AZ) 192.1 mm (7.56 inch) (BB) Boss

Note: Refer to Special Instruction, REHS1841, "General Welding Procedures" prior to performing any welding on the machine.

2. Prepare the area on the frame for welding. Remove all paint, dirt, oil, or debris from the area. Remove, relocate, or protect any components that may become damaged from nearby welding.

   Note: Locate block (2) that is located on the rear of the frame first. Then use the bracket and hardware from the ""Installation Procedure" " to locate block (2) on the inside right-hand side of the frame.

   Weld bosses (1), two blocks (2), and boss (3) to the frame.

   Repaint the welded area, as needed.

3. After boss (1) is located and welded to the rear of the frame, remove boss (BB) .

   Repaint the area, as needed.

Installation Procedure

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Illustration 28	g03850620
(1) 7Y-6338 Boss (4) 2S-4762 Clip (5) 125-8534 Plate As (6) 288-7158 Stud (W) Hose assembly (X) Bolt (Y) Washer (AA) Clip (AB) Hose assembly (AC) Bolt (AD) Washer (AE) Clipping

1. Secure hose assembly (W) to the existing block by using clip (4), and retained bolt (X) and washer (Y) .

2. Secure hose assembly (W) to hose assembly (AB) to boss (1) by using retained clip (AA), clipping (AE), bolt (AC), and washer (AD) .

3. Secure plate assembly (5) to the existing stud from the wiring group by using the existing nut and washer.

   Secure stud (6) to the existing boss on the frame.

   Note: Tighten stud (6) to 35 ± 5 N·m (26 ± 3.6 lb ft).

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Illustration 29	g03850948
(5) 125-8534 Plate As (6) 288-7158 Stud (7) 138-7500 Spacer (8) 8T-4172 Bolt (9) 8T-4121 Hard Washer (10) 136-4992 Spacer (L) Hose assembly (M) Clipping (S) Clipping (T) Bolt (U) Washer (V) Spacer (AF) Clipping (AJ) Nut (AK) Washer

4. Secure hose assembly (L) to the top boss on the frame by using spacer (7), bolt (8), hard washer (9), and retained clipping (M) .

   Secure hose assembly (L) to plate assembly (5) by using retained clipping (S), bolt (T), washer (U), and spacer (V) .

5. Secure hose assembly (AB) to stud (6) by using spacer (10), retained clipping (AF), nut (AJ), washer (AK) .

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Illustration 30	g03850953
(1) 7Y-6338 Boss (3) 178-7023 Boss (9) 8T-4121 Hard Washer (11) 5P-7468 Clip (12) 5P-7469 Clip (13) 5P-8444 Grommet (14) 8T-4136 Bolt (15) 204-2281 Cable Strap (D) Harness assembly (BC) Cable assembly

6. Secure harness assembly (D) to boss (1) and boss (3) by using two clips (11), two clips (12), two grommets (13), two bolts (14), and two hard washers (9) .

   Secure existing cable assembly (BC) to harness assembly (D) by using five cable straps (15) .

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Illustration 31	g03853236
(F) Hose assembly (1) 7Y-6338 Boss (3) 178-7023 Boss (9) 8T-4121 Hard Washer (14) 8T-4136 Bolt (16) 8T-4137 Bolt (17) 7D-7233 Clip (18) 8T-4198 Bolt (19) 287-0310 Spacer (20) 7X-2543 Bolt (21) 350-1571 Bracket As

7. If equipped, secure hose assembly (F) to the existing clipping locations by using four clips (17), five hard washers (9), two bolts (14), bolt (16), bolt (18), two spacers (19), bolt (20), and bracket assembly (21) .

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Illustration 32	g03853331
(22) 459-4024 Bracket (23) 8T-4184 Bolt (24) 198-4778 Hard Washer

8. Secure bracket (22) to the frame by using four bolts (23) and four hard washers (24) .

   Note: Do not final tighten bolts until all the exhaust components have been connected and adjusted properly.

   Note: After all the exhaust components have been installed, final tighten bolts (23) to 105 ± 20 N·m (77 ± 15 lb ft).

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Illustration 33	g03853333
(22) 459-4024 Bracket (25) 465-8077 Bracket As (26) 465-8072 Bracket As (27) 8T-4956 Bolt (28) 5P-1076 Hard Washer

9. Secure bracket assembly (25) and bracket assembly (26) to bracket (22) by using four bolts (27) and four hard washers (28) .

   Note: Do not final tighten bolts until all the exhaust components have been connected and adjusted properly.

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Illustration 34	g03853415
(25) 465-8077 Bracket As (26) 465-8072 Bracket As (C) Bracket assembly

10. Secure retained bracket assemblies (C) to bracket assembly (25) and bracket assembly (26) by using the retained hardware.

    Note: Do not final tighten bolts until all the exhaust components have been connected and adjusted properly.

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Illustration 35	g03853426
(A) Tube assembly (B) Tube assembly (BD) Bracket assembly

11. Reinstall tube assembly (A) and tube assembly (B) and any other removed exhaust components by using the retained hardware.

    Note: Ensure that existing bracket assembly (BD) is also secured.

    Note: Refer to Disassembly and Assembly, KENR8384, "Engine and Torque Converter - Remove and Install - High Altitude" for specific installation information.

    Note: After all the exhaust components have been connected and adjusted properly, final tighten all bolts.

797F XQ Configuration Rework Instructions

Removal Procedure

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Illustration 36	g03847489
(A) Tube assembly (B) Tube assembly

1. Remove and retain tube assembly (A) and tube assembly (B)

   Note: Refer to Disassembly and Assembly, KENR8384, "Engine and Torque Converter - Remove and Install" for specific removal information.

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Illustration 37	g03853879
(C) Bracket assembly (D) Bracket assembly (E) Bracket assembly

2. Remove and retain bracket assemblies (C), bracket assemblies (D), and all mounting hardware.

   Remove and discard bracket assembly (E) and all mounting hardware.

Fabrication Procedure

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Illustration 38	g03853919
(F) Block

1. Remove blocks (F) from the frame.

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Illustration 39	g03853882
(1) 441-1422 Block

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Illustration 40	g03855039
View of the inside right-hand frame (1) 441-1422 Block (G) 51.9 mm (2.04 inch) (H) 482.6 mm (19.00 inch) (for reference only)

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Illustration 41	g03855043
View of the inside rear of the frame (1) 441-1422 Block (J) 336.2 mm (13.23 inch) (K) 192.1 mm (7.56 inch)

Note: Refer to Special Instruction, REHS1841, "General Welding Procedures" prior to performing any welding on the machine.

2. Prepare the area on the frame for welding. Remove all paint, dirt, oil, or debris from the area. Remove, relocate, or protect any components that may become damaged from nearby welding.

   Note: Locate block (1) that is located on the rear of the frame first. Then use the bracket and hardware from the ""Installation Procedure" " to locate block (1) on the inside right-hand side of the frame.

   Weld bosses (1) to the frame.

   Repaint the welded area, as needed.

Installation Procedure

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Illustration 42	g03853924
(1) 441-1422 Block (2) 459-4025 Bracket (3) 8T-4184 Bolt (4) 198-4778 Hard Washer

1. Secure bracket (2) to blocks (1) by using four bolts (3) and four hard washers (4) .

   Note: Do not final tighten bolts until all the exhaust components have been connected and adjusted properly.

   Note: After all the exhaust components have been installed, final tighten bolts (19) to 105 ± 20 N·m (77 ± 15 lb ft).

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Illustration 43	g03854942
(2) 459-4025 Bracket (C) Bracket assembly (D) Bracket assembly

2. Secure retained bracket assemblies (C) and bracket assemblies (D) by using the retained hardware.

   Note: Do not final tighten bolts until all the exhaust components have been connected and adjusted properly.

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Illustration 44	g03854979
(A) Tube assembly (B) Tube assembly

3. Reinstall tube assembly (A) and tube assembly (B) and any other removed exhaust components by using the retained hardware.

   Note: Refer to Disassembly and Assembly, KENR8384, "Engine and Torque Converter - Remove and Install" for specific installation information.

   Note: After all the exhaust components have been connected and adjusted properly, final tighten all bolts.