NHTSA ID Number: 10253781
Manufacturer Communication Number: S3949 202404
TSB/Document Date: 2024-05-01
Summary
Service Campaign: Steering Stub Shaft Hardware Replacement
Service Campaign S3949
April 2024
Steering Stub Shaft Hardware Replacement
Service Category Service Department
Section Function Group 641
Technician Skill Level A
Market North America
Applicability
Mack
Model Years
2024-2025
Models
GR, PI
Introduction
Mack trucks has determined that certain GR, PI model trucks could have the incorrect steering
shaft support bearing mounting hardware installed. On affected vehicles follow the instructions
below to remove the steering shaft support bearing mounting hardware and replace with new
screws and nuts.
Production Change Information
This bulletin applies to vehicles built within the specified production changes below.
Brand
Engine
Emission Level
Starting Build Date Ending Build Date
Mack
MP8
EM-USA21
26-Januray-2024
1-Feburary-2024
Warranty Information
This repair is covered by an authorized Service Program. Reimbursement is
obtained through the normal claim handling process.
Claim Type (used only when uploading from the Dealer Bus. Sys.)
B
Main Labor Code
2551-03-03-01
Description
Hours
Campaign, General (0.1 X 4)
Causal Part
990951
SCC Authorization
Code
S3949
Expiration Date
April 30, 2025
0.4
Service Campaign S3949
April 2024
Steering Stub Shaft Hardware Replacement
Parts Information
Important Parts Note!
If flange bolt 995494 is not available, use flange bolt 995493 instead.
Part Numbers
Model
Part Names
Quantity
984754
GR
Flange Bolt
2
995494
PI
Flange Bolt
2
990951
GR/PI
Flange Nut
2
Calibration Information
N/A
Repair Procedure
1. Secure the vehicle for service.
2. Park the vehicle on a level surface with the steering wheel in the straight-ahead
position.
3. Apply the parking brake.
4. Place the gear lever in neutral.
5. Install wheel chocks.
6. Disconnect the cable from the negative terminal.
Service Campaign S3949
April 2024
Steering Stub Shaft Hardware Replacement
7. Unlatch and raise the hood.
8. Locate the two screws securing the steering shaft support bearing to the bracket.
9. Remove the two flange nuts and screws.
Service Campaign S3949
April 2024
Steering Stub Shaft Hardware Replacement
10. Discard the nuts and screws.
11. Install the new screw 984754 GR or 995494 PI and 990951 nuts.
12.
Tightening torque
Steering shaft, screws
85 ±5 Nm
(63 ±4 lbf⋅ft)
Service Campaign S3949
April 2024
Steering Stub Shaft Hardware Replacement
13. Lower and latch the hood.
14. Connect the cable to the negative terminal.
15. Remove the wheel chocks.
Service Campaign S3949
April 2024
Steering Stub Shaft Hardware Replacement
16. Release vehicle to service.
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TSB/Document ID: S3949 202404
Replacement Service Bulletin Number:
MFR Communication Date: 2024-04-18
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: STEERING
MFR Component System:
MFR Component Subsystem:
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