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Service bulletin LI27.60-P-076554

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id11032361
Published by NHTSA2026-05-06
Manufacturer's numberLI27.60-P-076554
Manufacturer's date2026-05-05
NHTSA componentPOWER TRAIN

NHTSA's summary

Complaint • Harsh 1-2, 2-3, and/or 3-4 shift • Jerky shifting • Jolting when accelerating from stop Cause Insufficient software application causing elevated K81/K27/B05 fill time adaptations and elevated torque adaptations for concerning shift. Note: Shift quality in E Performance models can be affected if the HV Battery state of charge (SOC) reaches 25% or below. Remedy Check VGS software level, and follow relevant remedy instructions. (see attachment) Vehicles with VGS software levels up to 22A: As of 4/18/2025, an aftersales software improvement has been released for model year 2023 C43 and SL43. This software has been implemented in production as of model year 2024, however this LI should still be followed if the concern is present. 232 - A0009025699 206 - A0009025599 Please ensure your Xentry machine is up to date with the latest Add Ons and continue with the following steps: Note: ALL steps must be performed to rectify concern 1. Perform software update all control units included in VGS software update. 2. Check transmission oil level and correct, if necessary (transmission oil temperature > 60 °C) 3. Perform Xentry Valve Flushing procedure at least 3x 4. Perform resetting of deceleration values (VGS > Special Procedures > Special procedure > Resetting learned values Deceleration mode) 5. Perform a standstill adaptation, then read out new EEPROM data 6. Perform driving adaptation(s) while adhering to the below parameters for at least 20-30 miles. Note: There is no menu in Xentry for this procedure. We recommend displaying the torque in the instrument cluster. If all below parameters are met at the time the shift, a driving adaptation will automatically occur. Harsh 1-2 Perform a driving adaptation of 4-5 (adapts K81 for the 1-2 shift) Harsh 2-3 Perform a driving adaptation of 6-7 (adapts B05 for the 2-3 shift) Harsh 3-4 Perform a driving adaptation of 3-4 (adapts K27 directly) - See attached PDF for min/max torque, and RPM parameters - Transmission oil temperature > 30°C (>86°F) - Level track (no incline/decline) - Slippery drive program - Display the torque in the instrument cluster - Constant engine torque - Do not shift via paddle If the vehicle returns and already had ALL steps in this LI performed on a previous visit, or has software level 23A and newer: Please submit a TIPS case to the Powertraininbox and ensure the following is included: - Initial Quick Test w/ Freeze Frame Data - VGS Control Unit Log - Initial EEPROM (before any adaptations or Xentry procedures were performed) - Detailed vehicle history of the complaint

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Transmission and driveline

Vehicles listed
MERCEDES-BENZ AMG C432023 to 2024
MERCEDES-BENZ AMG C43 4MATIC2023 to 2026
MERCEDES-BENZ AMG SL432026

Listing a model year does not mean every vehicle of it is concerned: the document says which.