NHTSA ID Number: 10240187
Manufacturer Communication Number: 20-NA-175
TSB/Document Date: 2023-08-02
Summary
This technical bulletin provides repair information to correct a customer concern of vertical misalignment between cab and pickup box on driver side of vehicle.
Bulletin No.:
Service Bulletin
Date:
20-NA-175
August, 2023
TECHNICAL
Subject:
Vertical Misalignment Between Cab and Pickup Box on Driver Side of Vehicle
Brand:
Model:
Model Year:
from
to
2019
2019
2020
2021
2022
2022
Silverado 1500
2023
2024
Silverado
2500HD/3500HD
2020
2020
Sierra 1500
(New Model)
2019
2019
Sierra 1500
2020
2021
Sierra 1500 (LIMITED RPO J21,
12th VIN Digit = 4
or less)
2022
2022
Sierra 1500
2023
2024
Sierra
2500HD/3500HD
2020
2020
Silverado 1500 (New
Model - 12th VIN
Digit = 7) - 4WD
VIN:
from
All
All
to
Silverado 1500
(New Model)
Silverado 1500
Chevrolet
Silverado 1500 (LTD, RPO J21, 12th
VIN Digit = 4 or less)
Silverado 1500 (RPO J22, 12th VIN
Digit = 5 or greater)
Sierra 1500 - (RPO
J22, 12th VIN Digit =
5 or greater)
Involved Region or Country
North America, Middle East, Israel, Palestine, Chile, Paraguay and Thailand.
Additional Options
Crew Cab and Extended Cab Models ONLY
Copyright 2023 General Motors LLC. All Rights Reserved.
Page 2
August, 2023
Bulletin No.: 20-NA-175
Condition
5645798
Some customers may comment on noticing anywhere from 2 –10 mm (0.08 – 0.4 in.)
vertical misalignment of the body feature line between the cab and the pickup box, on the
driver's side of vehicle.
Cause
The cause of the condition may be pickup box structure variation.
Correction
Realign the left side of the cab and install shim washers, following the steps in the
Service Procedure below.
Service Procedure
Important: Service agents must comply with all
International, Federal, State, Provincial, and/or
Local laws applicable to the activities it performs
under this bulletin, including but not limited to
handling, deploying, preparing, classifying,
packaging, marking, labeling, and shipping
dangerous goods. In the event of a conflict between
the procedures set forth in this bulletin and the
laws that apply to your dealership, you must follow
those applicable laws.
1. Verify the condition by visually checking, and
measuring, the body feature line variance, on the
left side of the vehicle.
2. Raise and support the vehicle. Refer to Lifting and
Jacking the Vehicle in SI.
5645799
5645804
Bulletin No.: 20-NA-175
August, 2023
Page 3
Important: We should never install more than 2 shim
washers in the rear to make the alignment, one will get
roughly 5 mm at the box/cab and two will get roughly
10 mm at box/cab interface.
6. Remove the jack stand from the cab.
5645800
3. Remove the 3 left side body mount bolts and
washers (1).
5645799
7. Perform the following procedure before installing
the body mount bolts (1).
7.1. Remove all traces of any of the original
adhesive patch from the bolt threads.
7.2. Clean the threads of the bolts with denatured
alcohol, or equivalent, and allow to dry.
7.3. Apply Threadlocker to the body mount bolts.
5645802
Note: For trucks with running boards, the jack can be
positioned below the running board bracket. For trucks
without running boards, position the jack below the cab
pinch weld and use a wood block to protect the paint,
and sheet metal.
4. Using a jack stand (1), raise the cab high enough
to achieve enough clearance to install the shim
washers between the body of the truck and the top
of each body mount.
5. Install shim washers to each body mount
location(s) as needed.
Note: Typically it will take 2 shim washers in the rear
mount to get a 10 mm adjustment in height at the body
line. If more than one washer shim is installed on the
rear body mount, you will need to put a single shim
washer on the mount at the B-Pillar.
5645806
8. Re-torque the 3 left side body mount bolts.
Tighten.
Tighten the bolts to 165 Nm (122 lb ft).
9. Remove the support and lower the vehicle.
10. Verify that the cab alignment condition has been
eliminated.
Page 4
August, 2023
Bulletin No.: 20-NA-175
Parts Information
Causal
Part
N/A
Description
Part
Number
Shim
84642724
Threadlocker
12345382
(U.S.)
10953489
(Canada)
Qty
As needed
Warranty Information
For vehicles repaired under the Bumper-to-Bumper
coverage (Canada Base Warranty coverage), use the
following labor operation. Reference the Applicable
Warranties section of Investigate Vehicle History (IVH)
for coverage information. Submit the cost of the
required washers as “Net Item Miscellaneous”.
Labor Operation
Description
Labor Time
1481418*
Realign Left Side of Cab to Pickup Box, Install Shim Washers
0.6 hr.
*This is a unique Labor Operation for Bulletin use only.
Version
5
Modified
Released - September 02, 2020
Revised October 27, 2020 – Removed Date Breakpoint
Revised December 21, 2020 – Added 2021 Model Year to Silverado/Sierra 1500.
Revised May 09, 2022 — Updated Shim Part number and Added 2022 Model Year.
Revised July 27, 2023 — Added 2023 and 2024 Model Years.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these
technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper
service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a
job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your
vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the
information.
WE SUPPORT VOLUNTARY
TECHNICIAN
CERTIFICATION
- 💯【Conta.ct us for Support Directly】If you met any...
- 🔥🔥🔥【2026 AUTEL FLAGSHIP MK900BT MK900-BT, NEW...
- 🚗【3000+ ACTIVE TESTS (50➡3000+), SAME AS MS...
- 🚗【40+ HOT SERVICES FOR 150 MAKES (28+➡40+)】Full...
- 🚗【OE ALL SYSTEM DIAGNOSE, AUTO SCAN 2.0: SCAN LICENSE...
- 【TURN OFF CEL】 This AL319 car scanner diagnostic tool...
- 【EXTENSIVE APPLICATION】 Autel AL319 Compatible with...
- 【FOR END USER & DIYERS】 This error code reader AL319 is...
- 【USER-FRIENDLY DESIGN】 This OBD2 scanner and check...
- 【HIGH-QUALITY SERVICES】 12 months war.ranty from the...
If the PDF is very large, it may not load in the preview below.
Some older TSBs had multiple PDFs — visit the NHTSA Website to view all PDFs.
If the TSB PDF does not show, download or view it on the NHTSA Website.
Click on the (+) Plus Sign
Then Click on Associated Document(s)
Search NHTSA Database for Recalls
Search NHTSA Database for Vehicle Investigations
View Latest Vehicle Investigations
Search NHTSA Database for Vehicle Complaints
View Latest Vehicle Complaints
TSB/Document ID: 20-NA-175
Replacement Service Bulletin Number:
MFR Communication Date: 2023-07-27
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: STRUCTURE
MFR Component System:
MFR Component Subsystem:
Previous TSB | Next TSB |
- [Notice] When you receive a used device, it may be a customer return resold by Amazon without inspection. You can exchange it for a new one through Amazon. As this situation is unavoidable, we sincerely apologize. For any issues, contacting us via Amazon's "Messages" is the best way. THINKSCAN 689BT Bidirectional Scan Tool Can Be Used Immediately After It is Turned On, Without Complicated Registration Process, Which is More Convenient & Quick.
- Full Bi-Directional Control & 3000+ Active Tests: Take control and test components like actuators, fuel injectors, relays, and cooling fans in real time. You’ll quickly see if the problem is in the part itself or the control module — saving you hours of guesswork and frustrating trial-and-error.
- Advanced ECU Coding Capabilities: Handle module matching and hidden feature activation with confidence. When you replace an ECU or want to customize settings, this obd2 scanner diagnostic bi directional tool gives you the professional-level capabilities you need without the dealership price tag.
- 34+ Useful Reset and Maintenance Functions: Complete everyday service tasks smoothly with a wide range of helpful reset and maintenance functions. Whether you’re keeping up with regular upkeep or tackling a specific job, this scanner makes maintenance simpler and less stressful for both DIYers and pros.
- Comprehensive Full System Diagnostics: Diagnose every major system — Engine, Transmission, ABS, SRS, TPMS, and more — all in one place. Finally stop wondering if you’re missing something important; get the full picture and clear codes with ease.
- Top Reasons to Choose the D7S OBD2 Scanner: XTOOL D7S car scan tool, an upgrade of XTOOL D7, offers comprehensive features for automotive technicians, workshops, and DIY enthusiasts 1. Upgraded Hardware: 2+64GB memory, rear camera, intuitive interface, foldable bracket 2. Complete Diagnostics: FCA
Autoauth, OE-level all system scan, 39+ maintenance services, 4K+ bidirectional, CANFD/DoIP protocol 3. Advanced Capabilities: ECU c0ding, PMI functions 4. Wide Compatibility: Support 10,000+ models, covering 99% vehicle brands 5. Multi-language: Available in 22+ languages, No IP Restrictions 6. 3-Year Updates: Save 300 bucks on software updates for the latest features and optimizations - 2026 Upgraded D7S Car Scanner Features: The newly 2026 D7S V2.0 scanner for car brings exciting features for advanced vehicle diagnostics and enhanced user experience 1. FCA AutoAuth: Now supports FCA SGW module for Chrysler, for Jeep, for Dodge (2018+), for Fiat (2017+), enabling faster vehicle communication without gateway restrictions 2. PMI (Offline ECU Pr0gramming): Allows for Ford, for Lincoln, and for Mazda ECU pr0gramming for new modules 3. Optimized Diagnostic Report 2.0: Personalized reports with logos and customer info for auto shops. Note: Compatibility varies by cars, please check before order
- 39+ Services/Resets/Adaptations/Relearns/Calibrations: XTOOL D7S full system car scanner diagnostic tool tackles 99% of common car issues through its 36+ special functions, including Oil Reset, EPB, SAS, BMS, Throttle Reset, Injector C0ding, ABS Bleed, TPMS Reset, Power Balance, etc and also covers specific-vehicle functions like Crank Sensor Relearn, ABS Initialization, Cylinder Power Balance, Fuel Trim Reset, Idle Relearn etc. This car diagnostic scanner enhances efficiency, making repairs and maintenance hassle-free. Tip: DO NOT for All vehicles, please check compatibility first
- Cost-effective ECU C0ding Scan Tool for Specific Brands: Enhance your vehicle's performance with XTOOL D7S! This obd2 scanner all systems bidirectional offers advanced capabilities at an affordable price, supports online for BMW, for Benz and offline for BENZ, for MIT, along with PMI functions for Ford, for Mazda, and for Lincoln. Ideal for technicians and DIY enthusiasts, this automotive scanner diagnostic tool optimizes vehicle performance and enhances the driving experience. Note: Not for all cars and modules, please send car VIN to check the compatibility before purchase
- OE All System Diagnostic & 8 Pids Graphing: XTOOL D7S is a comprehensive all system bi directional obd2 scanner that delivers dealer-level diagnostics, completely controlling over your vehicle’s performance and health. This automotive scan tool can read and clear DTCs, view live data and ECU information, retrieve freeze frames, and perform active tests and full obd2 functions. This bi-directional scan tool can can identify your vehicle's make, model, and year information with just one click and show up to 8 PIDs live data with options for CSV viewing, playback, and recording for in-depth analysis. It is easy-to-use for both professionals and beginners, helping pinpoint issues efficiently
- 【✅Compared to BOSSCOMM IF742, IF745 Offers Full-System Diagnostics】The BOSSCOMM IF745 car diagnostic scanner is an upgraded model of IF742. In addition to supporting all OBD2 Code Reader functions and 6 reset options (ABS/EPB/SAS/BMS/Oil/Throttle), it expands diagnostics from 4 systems (Check Engine/ABS/SRS/Transmission) to vehicle All systems, including Steering, Suspension, and Body Electronics. This provides deeper, more comprehensive diagnostic capabilities.
- 【✨10 OBD2 Functions】The BOSSCOMM IF745 scan tool’s DTC Lookup instantly translates fault codes into user-friendly explanations, its I/M Readiness feature streamlines emissions testing with a single tap, and Freeze Frame lets you pinpoint the exact moment of a fault for in-depth root-cause diagnosis. Combined with a live data dashboard and advanced diagnostics (O2S, OBMon, EVAP), it delivers comprehensive insights for confident troubleshooting.
- 【✨Deep Diagnostics for All Vehicle System Modules】Beyond code reading/clearing and ECU information retrieval, our all-in-one data stream feature lets you inspect all current fault codes and their locations across the vehicle’s systems. This vehicle code reader helps you turn off dashboard warning lights and perform a comprehensive self-check of your car at home—no more back-and-forth trips to the repair shop or hefty inspection fees.
- 【✨6 Essential Resets: ABS Bleeding, Oil, EPB, SAS, Throttle, BMS】The BOSSCOMM IF745 obd2 scanner diagnostic tool swiftly purges air from brake lines to restore braking sensitivity, fine-tunes maintenance cycles to eliminate false alerts, resolves parking brake issues with one-click control, recalibrates steering sensors for stability, optimizes engine idling/acceleration for smoother performance, and deeply resets battery systems to extend lifespan and range via precise parameter adjustments.❗NOTE: Does NOT support bidirectional control, coding, or programming.
- 【✨10,000+ Car Models, AutoVIN, 13 Languages】The BOSSCOMM IF745 vehicle scanner diagnostic tool covers 73+ global car brands and offers support in 13 languages, making it perfect for DIYers, auto mechanics, or as a thoughtful gift. With a single-click AutoVIN feature, it instantly retrieves vehicle serial numbers, streamlining diagnostics for users globally. This adaptable tool balances user-friendliness with precision, catering to both personal and professional requirements.✅Unsure about compatibility? Compatibility will vary on vehicles' model and year, pls reach us via 📧 [email protected] 📧 before purchase.
This product presentation was made with AAWP plugin.