NHTSA ID Number: 10194436
Manufacturer Communication Number: TSB 21-2155
Summary
Some 2020-2021 Mustang Shelby GT500 vehicles may exhibit a cracking on the hood inner panel. The crack is a cosmetic condition, not a structural concern. This may be due to a variation in production of the hood. To correct the condition, follow the Service Procedure to repair the hood crack.
Model:
2020-2021 Mustang Shelby GT500
Issue: Some 2020-2021 Mustang Shelby GT500 vehicles may exhibit a cracking on the hood inner panel. The crack is a cosmetic condition, not a structural concern. This may be due to a variation in production of the hood. To correct the condition, follow the Service Procedure to repair the hood crack.
Action: Follow the Service Procedure steps to correct the condition on vehicles that meet all of the following criteria:
- 2020-2021 Mustang Shelby GT500
- Cracked inner hood panel
NOTE:
Parts
| Service Part Number | Quantity | Description |
| Obtain Locally | As Needed | Body Filler |
| Obtain Locally | As Needed | 3M™ Ultra Fine Finishing Pad Or Equivalent |
| Obtain Locally | As Needed | 400-600 Grit Sandpaper |
Service Procedure
Figure 1
Figure 2
Figure 3
1. Lightly sand the affected area using 400-600 grit sandpaper.
2. Prepare the cracked surface by spraying an alcohol/water mixture on a microfiber cloth and using it to clean the surface.
3. Create typical body filler by mixing resin and hardener following manufacturer specifications. Mix enough to last 2 minutes.
4. Using a plastic blade, apply thin layers to fill the void. Use a front, back, and side to side motion. Make sure the material is bordered on all sides.
5. Allow the body filler to dry for a minimum of 15 minutes or as specified by manufacturer.
6. Use 3M™ Ultra Fine Finishing Pad or equivalent to sand. This will level the body filler down with the SMC substrate. The 3M™ Ultra Fine Finishing Pad or equivalent will finesse over the sanding marks from Step 1.
7. Spot paint the under hood affected area that was repaired. Mix and apply base coat and clear coat following the Ford
approved paint system technical information.
2 Affected Products
Vehicle
1 Associated Document
Manufacturer Communications
21-2155
17 May 2021
MC-10194436-0001.pdf 151.974KB
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Last update on 2026-06-20 / Affiliate links / Images from Amazon Product Advertising API
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Warranty Status: Eligible under provisions of New Vehicle Limited Warranty (NVLW)/Service Part Warranty (SPW)/Special Service Part (SSP)/Extended Service Plan (ESP) coverage. Limits/policies/prior approvals are not altered by a TSB. NVLW/SPW/SSP/ESP coverage limits are determined by the identified causal part and verified using the OASIS part coverage tool. Labor Times Description Operation No. Time 2020-2021 Mustang Shelby GT500: Repair Inner Hood Panel And Apply Base Coat And Clear Coat Following the Service Procedure MT212155 Actual Time Repair/Claim Coding Causal Part: 16612 Condition Code: 01
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