{"nhtsa_id":11018588,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2025-05-27","date":"2025-05-22","document_id":"LI61.20-P-077105","mfr_campaign":null,"replaces":null,"component":"STRUCTURE:BODY","mfr_system":null,"summary":"Complaint Cracking/clicking noise from underbody when driving slowly (around curves); see attachment. Cause Potential causes: • Assembly of the underfloor paneling with unloaded body (results in tension after compression of vehicle in K0- design level) • Relative movement between front and rear engine compartment lining • Torque loss of the screw connection • Accumulation of stones and dirt Remedy • Screw connection in K0-design level (vehicle sitting on ground on it's own weight) and taking into account the correct screw sequence • Additional screw connection points (minimization of relative movement) • Increase in tightening torque • Integration of spacer rings (reduction of accumulation of stones and dirt) In order to rule out that other component parts may be responsible for the noise, remove the underfloor paneling first. If the noise complaints are NO LONGER present after removal, proceed with underfloor paneling rework. Underfloor paneling rework 1. Order after-sales kit with item number A2326207003 for the rework. 2. After receiving the after-sales kit (A2326207003), check the contents: 22 screws (A0109902604) / 14 rivet nuts (A0009902349) / 4 spacer washers (A2326207203). If the content is complete, start rework in the next step. 3. Disassemble underfloor paneling. If front and rear engine compartment lining are bonded to one another, order new parts (A2326201101, A2326268900). 4. Clean underfloor paneling and integral carrier. 5. Mark four additional screw connection points on the front engine compartment lining (see attachment 1). See appendix 2 for dimensions. 6. Drill holes with d=9 mm on the markings. 7. Screw front and rear engine compartment lining together using the screw connection points already available (see attachment 3). Both linings are therefore aligned to one another. Important: Pay attention to alignment of the elongated holes on the external edges. 8. Drill into the rear engine compartment lining using the four additional holes with d=9 mm (see attachment 4). 9. Disassemble front and rear engine compartment lining. 10. Drill out three existing rivet nuts with d=9 mm (see attachment 5). 11. Insert seven new rivet nuts (A0009902349) (see attachment 6). 12. Drill out seven existing rivet nuts in the integral carrier with d=9 mm (see attachment 7). Caution: Do not damage integral carrier. 13. Remove remaining rivets that have fallen off from the integral carrier using a magnetic tube (see attachment 8). 14. Insert new rivet nuts (A0009902349) in the integral carrier (see attachment 9). 15. Fix four spacer rings (A2326207203) in place using bonding points between underfloor paneling and integral carrier (for position, see attachment 10 and attachment 11). Caution: No adhesive can be applied to the contact areas (risk of torque loss). 16. Install underfloor paneling on vehicle with 16 Nm (observe screw sequence in attachment 12). Important: Use screw item number A0109902604.","document":{"url":"https://static.nhtsa.gov/odi/tsbs/2025/MC-11018588-0001.pdf","alternate_url":"https://static.nhtsa.gov/odi/tsbs/2025/MC-11018588-9999.pdf","confirmed":false},"url":"https://open.wenmarpro.com/bulletins/11018588","components":[{"id":"structure-body","name":"Body and frame","parent":null}],"codes":[],"topics":[],"vehicles":[{"make":"MERCEDES-BENZ","model":"AMG GT55","year_from":2024,"year_to":2024,"match":"base","vehicle_ids":["2024_mercedes-benz_amg-gt"]},{"make":"MERCEDES-BENZ","model":"AMG GT63","year_from":2024,"year_to":2024,"match":"base","vehicle_ids":["2024_mercedes-benz_amg-gt"]},{"make":"MERCEDES-BENZ","model":"AMG GT63 S E","year_from":2024,"year_to":2024,"match":"base","vehicle_ids":["2024_mercedes-benz_amg-gt"]},{"make":"MERCEDES-BENZ","model":"AMG SL43","year_from":2022,"year_to":2024,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG SL53E","year_from":2024,"year_to":2024,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG SL55","year_from":2022,"year_to":2024,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG SL55 4MATIC+","year_from":2023,"year_to":2023,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG SL63","year_from":2022,"year_to":2023,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG SL63 4MATIC+","year_from":2023,"year_to":2023,"match":null,"vehicle_ids":[]},{"make":"MERCEDES-BENZ","model":"AMG SL63 S E","year_from":2024,"year_to":2025,"match":null,"vehicle_ids":[]}],"as_of":"2026-10-19","note":"A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.","attribution":[]}