Technical Service Information
TSI–13–47–01
Date: May 2013
Subject File: Bus Body
Subject: Passenger Seat Back Pan Inspection and Repair
Model: BE, CE, RE School and Commercial Bus
Start Date: February 2010 End Date: August 2011

DESCRIPTION
NOTE: Repair of the back pan attachment is the recommended repair rather than replacement of the
back assembly.
This TSI applies to buses built February 2010 to August 2011 with feature code 48USV experiencing
complaints of seat back pan rattles or bowing conditions. These instructions outline an inspection of the back
pan-to-frame welds, which may indicate back pan attachment point failures on seats with increased fore
and aft pressure applied to the back pan.

PARTS INFORMATION
Table 1.

Tools Information
Description

Part Number

Cordless Drill

Obtain Locally

Drill Bit, #23

Obtain Locally

Crosstip Bit

Obtain Locally

Table 2.

Parts Information
Part Number
435445001

Description

Quantity
As Required

Screw, #10

© 2013 Navistar, Inc. All rights reserved. All marks are trademarks of their respective owners.

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SERVICE PROCEDURE
WARNING: Park vehicle on hard flat surface, turn the engine off, set the parking brake, and
block the wheels to prevent the vehicle from moving in both directions. Failure to do so may result
in property damage, personal injury, and / or death.

WARNING: If the vehicle must be raised, do not work under the vehicle supported only by
jacks. Jacks can slip or fall over, potentially resulting in property damage, personal injury, and / or
death.

WARNING: Always wear safe eye protection when performing vehicle maintenance. Failure
to do so may result in personal injury and / or death.

WARNING: Keep flames or sparks away from vehicle and do not smoke while servicing
the vehicle’s batteries. Batteries expel explosive gases. Failure to do so may result in property
damage, personal injury, and / or death.

WARNING: Remove the ground cable from the negative terminal of the battery box before
disconnecting any electrical components. Always connect the ground cable last. Failure to do so
may result in property damage, personal injury, and / or death.

1. Bring bus into shop and park on flat surface.
2. Shift transmission to Park or Neutral, set parking brake, and install wheel chocks.

TSI–13–47–01

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SERVICE PROCEDURE (CONT.)

Figure 1.

Bow in Seat Back.
1. Seat back
2. Seat cushion
3. Bowing

NOTE: To be most efficient, work from front to rear of bus for visual inspection of seat backs and rear
to front while removing upholstery and foam assemblies.
3. Visually inspect passenger seat back (Figure 1, Item 1) for bowing (Figure 1, Item 3) between seat back
and seat cushion (Figure 1, Item 2).
NOTE: It is common for all seats to have a slight rattle or noise condition when performing this test;
however, if the back pan is loose, a distinctive rattle will be present.
4. Inspect seat back (Figure 1, Item 1) by rapping on top face of seat back with a hand or fist to listen
for a rattle in back pan.
5. Unlatch and lift seat cushion (Figure 1, Item 2) of each seat back (Figure 1, Item 1) suspected of needing
repair.
NOTE: Upholstery is attached at lower back of seat back with j-clip.
6. Unsnap j-clip, loosen foam from frame, and slide off upholstery and foam as assembly.
7. Install and latch seat cushion (Figure 1, Item 2) of each seat back (Figure 1, Item 1) needing repair and
place upholstery and foam assembly on floor in front of seat.

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TSI–13–47–01

SERVICE PROCEDURE (CONT.)

Figure 2.

Back Pan Welds.
1. Back pan frame
2. Back pan
3. Weld

8. Inspect welds (Figure 2, Item 3) on back pan (Figure 2, Item 2) and back pan frame (Figure 2, Item 1) to
confirm back pan failure. If no weld failure is found, reinstall upholstery and foam assembly and snap j-clip

TSI–13–47–01

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SERVICE PROCEDURE (CONT.)

Figure 3.

Back Pan.
1.
2.
3.
4.
5.

Back pan frame
Back pan
Middle back pan tab
Lower back pan tab
Screw (10)

9. If bent, straighten back pan (Figure 3, Item 2) to fit it to original location.
NOTE: Drill hole in front side of back pan frame only, not through entire frame.
10. Mark 10 screw locations, and drill through middle and lower back pan tabs (Figure 3, Items 3 and 4) of
back pan (Figure 3, Item 2) and back pan frame (Figure 3, Item 1).
11. To increase technician efficiency, repeat Steps 9 and 10 for each seat back pan needing repair.
NOTE: When repairing a back pan with weld failures, install three screws in each lower tab and two
screws in each middle tab regardless of the original weld failure location. No screws are required in the
back pan to round tube area unless a weld failure is found. If a weld failure in this area is found, drill
and install one screw per failed weld location.
12. Secure back pan (Figure 3, Item 2) to back pan frame (Figure 3, Item 1) with 10 screws (Figure 3, Item
5) on each back pan drilled.
13. Unlatch and lift seat cushion (Figure 1, Item 2) of each seat back (Figure 1, Item 1) repaired.
14. Install seat back upholstery and foam assemblies on each seat repaired and snap j-clip.

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TSI–13–47–01

SERVICE PROCEDURE (CONT.)
15. Use vacuum or suitable air supply to remove drill shavings from work area.
16. Install and latch seat cushion (Figure 1, Item 2) of each seat back (Figure 1, Item 1) repaired.
17. Remove wheel chocks.

TSI–13–47–01

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