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Service bulletins for the 2026 Mercedes-Benz AMG GT

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.

100 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

Only bulletins with component: Transmission and driveline are shown. Show all

Bulletins, newest first
LI35.30-P-0585662026-07-14. Service bulletin. POWER TRAIN. Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end). The noise is heard once in each instance when changing direction of travel. Note: Sound file in attachment Cause If the complaint is eliminated by experimentally loosening the outboard collar nut (by 1 turn), the problem is due to cracking of the microweld between the wheel bearing inner race and the joint housing of the side shaft. Note: The collar nut must always be replaced after being loosened. See also LI33.20-P-078406 Remedy Coat contact surface of side shaft with wheel bearing with Molykote paint. To do this, proceed as follows: 1. Remove side shafts 2. Clean contact surface A (see image file in attachment "Outer joint housing before") before coating with Molykote, using "spirit" (free of dust and grease) 3. Coat contact surface A (see image file in attachment "Outer joint housing after") with Molykote and leave to dry for "one hour" in removed condition 4. Reinstall side shafts Note: Before using the antifriction coating (Molykote), stir it or shake it thoroughly for (at least 1 minute).
PSL-NCU Return Parts 5/152026-05-18. Other. SUSPENSION; POWER TRAIN. The part numbers listed in the chart below should no longer be installed, and any existing stock must be returned to your facing PDC. The deadline for all dealer returns is no later than Thursday, June 4, 2026. After June 4th, returns of these parts will no longer be accepted. These parts should be returned via ZSR Special Return, using item category SCM Authorized Part Return. Please include a copy of this NCU as your authorization to return these parts. This procedure will not affect your return allowance. All returned parts will be replaced in accordance with the chart provided below.
NCU - 20251200092026-03-14. Service campaign. ELECTRICAL SYSTEM; POWER TRAIN. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the drivetrain control unit does not meet current production specifications. The system may experience an excessively high quiescent current draw on the vehicle, which could lead to an increased discharge of the 12V battery. MBUSA will conduct a service campaign. An authorized Mercedes-Benz dealer will update the drivetrain control unit software.
LI27.60-P-0789982026-02-13. Service bulletin. POWER TRAIN. Complaint A noticeable jerk or jolt from the transmission occurs in electric driving mode (E mode), between 20-40 mph. Concern is mainly felt when coasting. Cause Parameters of the 5–4 neutral downshift (the shift method used in EV operation). Remedy This shift concern is considered normal for vehicles with this drivetrain. Hardware replacement does not change the root cause of the concern, as the observed shift behavior is characteristic of normal system function rather than a component‑related fault. The following adaptations may improve the shift quality: 1. Check transmission oil level (transmission oil temperature > 60°C) 2. Flush valves via Xentry procedure 3. Perform standstill adaptation 4. Perform driving adaptations for the 5–4 shift while following the below parameters: - Drive program: Slippery - Display torque in the instrument cluster - Do not shift using the paddles During coasting downshift 5-4: - Torque between –90 and –15 Nm (-66 and -11 ft-lb) - Maximum engine speed: 1,300 rpm
NCU - 20251200092026-01-16. Service campaign. POWER TRAIN. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the drivetrain control unit does not meet current production specifications. The system may experience an excessively high quiescent current draw on the vehicle, which could lead to an increased discharge of the 12V battery. MBUSA will conduct a service campaign. An authorized Mercedes-Benz dealer will update the drivetrain control unit software.
LI27.35-P-0801602025-12-24. Service bulletin. POWER TRAIN. Complaint (Original LI document #: LI27.35-P-079039) Clicking noises from the electro-hydraulic control unit (EHS) when the vehicle is stationary and ECO Start/Stop is active (combustion engine is off). The noise is more noticeable outside the vehicle and in acoustically shielded areas such as closed rooms or garages. Cause The noise in the valve body (EHS) is caused by superimposed pressure peaks acting on the valves. This phenomenon occurs only after a certain running-in period due to the influence of micro-contamination in the valve bores. Remedy A hardware modification of the electro-hydraulic control unit (EHS) is currently being implemented (no change to the part number). This will be incorporated into series production and as a spare part starting from 12/2025. This is only a comfort-related complaint and has no impact on the functionality or service life of the transmission. For sensitive customers, the following measures can be performed: 1. Replace the electro-hydraulic control unit (EHS), the oil pan, and the transmission fluid. - Ensure all oil guide pipes are installed in the new valve body to prevent a new concern after replacement. (See attached location guide)
LI33.30-P-0566652025-11-20. Service bulletin. POWER TRAIN. Complaint Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end). The clunk is heard once when changing from forward to reverse (and vice versa). Note: Sound file in attachment Cause If the complaint is eliminated by experimentally loosening the outboard collar nut (by 1 turn), the problem is due to micromovement in the connection between the wheel bearing inner race and the joint housing of the side shaft. Note: The collar nut must always be replaced after being loosened and must be tightened to the specified torque. Remedy Coat contact surface of side shaft with wheel bearing with Molykote paint. To do this, proceed as follows: 1. Remove outboard side shafts (extract outer joint gearing from wheel hub) 2. Clean contact surface A (see picture file in attachment "Outer joint housing before") before coating with Molykote, using "spirit" (free of dust and grease) 3. Coat contact surface A (see image file in attachment "Outer joint housing after") using Molykote and leave to dry for one hour in removed condition 4. Reinstall side shafts Note: Before using the antifriction coating (Molykote), stir or shake it well (for at least 1 minute).
LI27.35-P-0799712025-11-11. Service bulletin. POWER TRAIN. Complaint Possible complaints about shift quality, issues with learning the park lock, and slipping/rinse entries in the EEPROM or Transmission Health system following the replacement of the below components: - The electrohydraulic control unit (EHS valve body) in transmission 725.0/725.1 - The repair kit for the control unit (VGS) in transmission 725.0 Cause Missing, incorrectly installed, or damaged guide tubes on the EHS valve body. Remedy Check for the correct installation of the guide tubes (refer to attachments under “Cause”), correct installation if necessary. Parts Catalog References: NAG3M 725.1 AND NAG3C 725.0 (AMG only): Part numbers 100, 120, 150, 160 NAG3C 725.0 (Non AMG): Part numbers 280, 290, 330, 340 NOTE: If any of these guide tubes are not installed and the vehicle is driven, it will create several rinse and slipping events in the EEPROM data. These values caused by incorrect installation need to be erased to prevent future misdiagnosis. Submit a TIPS case to the Powertrain inbox with the following to receive the necessary reset password: - Initial Quick Test w/ Freeze frame data - VGS Control Unit Log - IPR Result - Initial EEPROM data (before repairs) - Latest EEPROM data - Photo of oil level ultrasonic measurement next to XENTRY specifications Please provide detail regarding the reasoning for the initial replacement in your workshop findings and measures performed. (This topic was covered in the July 2022 and July 2024 Passenger Car Tech Topics)
LI27.10-P-0758692025-11-06. Service bulletin. POWER TRAIN. Complaint Only vehicles with a variable transfer case are affected. This can be identified through control unit N45 or N15/7 in the quick test. When accelerating with light load, vibrations or jolting sensation may come from the drivetrain. It may be mistaken for a harsh shift. Cause Modified oil quality of the transfer case over time Remedy 1. Check initial quick test for faults in the following control units. N45 or N15/7 - All-wheel drive (ARS) N127 - 'Drivetrain' (PTCU) control unit Y3/8 - Transmission control for 9-gear transmission (VGS) N3/10 - Engine electronics for combustion engine If faults are present: Process them as per the guided test in Xentry. If no faults are present: 2. Check the transmission oil level If the oil level is correct: 3. Unplug the connector for the transfer cases control unit and reassess the vehicle on a subsequent test drive If the complaint no longer occurs with the control unit disconnected: 4. Perform an oil change of the transfer case according to WIS specifications - Collect an oil sample of the original fluid 5. Complete all transfer case Tech-in processes located under VG Control Unit > Adaptations - Resetting the oil service data - Calibration of N15/7 5. Perform road test of vehicle to bring transmission to operating temperature ( >60C ) 6. Operate vehicle in full circle with steering at full lock - 5x to the left - 5x to the right 7. Perform an extended 200mi road test to ensure the clutches are properly conditioned with the new oil. 8. Reassess the concern and release the vehicle if no longer present. If the concern continues to occur with the control unit disconnected or after the above steps have been performed, please submit a TIPS case to the Powertrain inbox with the following information: - Initial quick test with fault freeze frame data - Initial transmission EEPROM data - VGS and Transfer Case Control Unit Log (N45 or N15/7) - Photo of the original oil condition - What color was the fluid drained from the transfer case before the oil change? - Was an oil sample collected, and can you provide a photo of the original fluid? - What color and part number fluid was used during the oil change? - How far was the vehicle driven after?
LI35.31-P-0798472025-10-07. Service bulletin. POWER TRAIN. Complaint Complaints of oil leaking from rear differential oil pan area. Cause In the groove where the pan seal is placed, there may be imperfections (porosity) in the casting causing fluid to leak past the seal. The supplier states this only affects rear differentials with 2023 production date. The production date can be found stamped on the housing cover (see attachment). Remedy 1. Follow the attached instructions to inspect the rear differential cover for porosity. 2. Repair the vehicle with the applicable repair kit for the chassis. - The new oil pans that come with the repair kit should be produced in 2024 and not have this issue. *When submitting the claim, please reference this LI document and if porosity was found.*
LI27.19-P-0725882025-09-18. Service bulletin. POWER TRAIN. Complaint Transmission control unit Y3/8n4 (fully integrated transmission control unit (VGS)) not listed in quick test and/or no communication possible with VGS. Cause Transmission control unit Y3/8n4 Remedy For vehicles with 722.9 transmission: Ensure LI54.15-P-057373 is performed before replacing any component parts. After processing and complying with the above document(s): 1. Perform an ignition reset on Y3/8n4 (VGS) 2. Inspect transmission connector for loose connections, damaged wiring or pins and any other concerns If communication with the VGS cannot be established, the complete valve body ('electrohydraulic controller unit (EHS)') must be replaced. Installation of a VGS repair kit is not permitted in this case as it is not possible to transfer the necessary valve characteristics without communication with the original control unit.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.