NHTSA ID Number: 10198864
Manufacturer Communication Number: 21NA017
Summary
This technical bulletin provides repair information to correct a customer concern of a rattle or creak noise heard coming from driver left rear quarter panel area when driving over bumps.
1 Affected Product
Vehicle
| MAKE | MODEL | YEAR |
| CHEVROLET | TRAILBLAZER | 2021 |
Condition
Some customers may comment on a rattle or creak noise heard coming from the driver left rear quarter panel area when driving over bumps.
The noise may travel around the B and C-pillars, and is best heard from behind the driver.
Cause
The cause of the condition may be a quality issue of inefficient and/or mis-located spot welds at the C-pillar upper, inner structure panels.
Correction
Upon verifying the Condition, drill 3 holes through ONLY the C-pillar upper, inner structure and Mig weld the hole locations following the steps in the Service Procedure below.
| Description | Part Number | Qty |
| SEM – Rust Preventor Cavity Wax | 39573 | As needed |
| SEM – EzCOAT | 62233
SEM 62233 Light Green Ez Coat - 12 oz.
Last update on 2026-06-19 / Affiliate links / Images from Amazon Product Advertising API |
SEOCONTENT-START
Copyright 2021 General Motors
LLC. All Rights Reserved. Service Bulletin Bulletin No.: 21-NA-017 Date: May, 2021 TECHNICAL Subject: Rattle or Creak Noise Heard Coming From Driver Left Rear Quarter Panel Area When Driving Over Bumps Brand: Model: Model Year: VIN: Engine: Transmission: from to from to Chevrolet
Trailblazer (VIN M) 2021 2021 All All Involved Region or Country North America, Additional Options (RPOs) Condition Some customers may comment on a rattle or creak noise heard coming from the driver left rear quarter panel area when driving over bumps. The noise may travel around the B and C-pillars, and is best heard from behind the driver. Cause The cause of the condition may be a quality issue of inefficient and/or mis-located spot welds at the C-pillar upper, inner structure panels. Correction Upon verifying the Condition, drill 3 holes through ONLY the C-pillar upper, inner structure and Mig weld the hole locations following the steps in the Service Procedure below. Service Procedure 1. Disable the SIR system. Refer to SIR Disabling and Enabling, in SI. 5721193 2. Remove the headliner and left rear row seat roof rail airbag. Refer to Front and Rear Row Roof Rail Airbag Replacement, in SI. Page 2 May, 2021 Bulletin No.: 21-NA-017 5836229 3. Locate the 3 forward – most spot weld and hole locations, and mark drill locations, approximately 10 mm (0.40 in) (1) forward of them. 5721196 4. Using an 8mm (5/16 inch) drill bit, drill through ONLY the inner sheet metal panel at those 3 locations. 5721197 5. De-burr and prep the inner panel for Mig welding. Bulletin No.: 21-NA-017 May, 2021 Page 3 5721198 6. Mig weld the drilled hole areas. 5721203 5721202 7. Apply *SEM cavity wax to the inside of the inner panel, and *SEM EzCOAT to the outside of the inner panel. 8. Road test the vehicle, to ensure the noise has been eliminated. Page 4 May, 2021 Bulletin No.: 21-NA-017 5241734 9. Reinstall the left rear row seat roof rail airbag (3) and the headliner. Refer to Front and Rear Row Roof Rail Airbag Replacement, in SI. 10. Enable the SIR system. Refer to SIR Disabling and Enabling, in SI. * We believe this source and their products to be reliable. There may be additional manufacturers of such products/materials. General Motors
does not endorse, indicate any preference for, or assume any responsibility for the products or material from this firm or for any such items that may be available from other sources. Parts Information For ordering adhesive material, contact SEM Customer Care at #866–327–7829, or [email protected], or at SEM Tech Support at #800-831-1122, or [email protected]. Causal Part Description Part Number Qty N/A SEM – Rust Preventor Cavity Wax 39573 As needed SEM – EzCOAT 62233 Bulletin No.: 21-NA-017 May, 2021 Page 5 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. Labor Operation Description Labor Time 1481488* Drill and Mig Weld Left C-Pillar Inner Structure 2.3 hr *This is a unique Labor Operation for Bulletin use only. Version 2 Modified Released January 27, 2021. Revised May 19, 2021 – Added Additional Weld Location to Service Procedure, Road Test and Increased Labor Time. 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
SEOCONTENT-END
1 Associated Document
Manufacturer Communications
Bulletin No.: 21-NA-017
Date: May, 2021
MC-10198864-9999.pdf 205.629KB
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Last update on 2026-06-19 / Affiliate links / Images from Amazon Product Advertising API
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