2017 Mercedes-Benz GLS 550

Feel unsafe fuel rails and more where recalled in April 2022 Not all gls550 were recalled at the time due to no reason Drive to Florida with my wife and kids and car gave up on the side of a bridge hwy over the ocean We were stuck car smelt like gas and wouldn’t turn on we had nowhere to get out on a 25ft bridge with no ac no emergency lanes with 5 kids all under age of 6

NHTSA ID

11678641

Incident

Aug 2, 2025

We had our Mercedes GLS550 2017 with 59,295 overheat and call for immediate shut down on the Massachusetts Turnpike with my wife and child in the car. It was quite a dangerous situation because the failure caused by hose assembly 166-830-15-00 clamp (as described by the dealer as the reason for the loss of fluid and hose failure) caused almost an immediate overheating. The service advisor stated that it is "a quite common failure". I was quite suspicious, because just 11 days prior and 138 miles prior they had performed an Oil Change (Service B9), and thought their mechanic must have damaged the hose fitting they claimed broke. When I looked at the schematic, the fitting is quite close to the Oil Filter Cap, so I assumed that the mechanic accidentally knocked the plastic clamp and broke it. However, they said this was a "normal failure" on these cars. I am a data scientist and have requested failure rates for similar autos in the data cohorts of 50,000, to 60,000 miles and 4 to 5 years old. It woudl be also nice to see if there was data available that included Post B( service visits for the same failures. I was surprised they tracked this data since I was told it was a common failure of this part. Looking at the design of where the host runs, it is certainly exposed to a mechanics tools removing the Oil Filter wrench. If this is common, I would like to help other families with young children being stranded by the side of a busy highway. In this case, I told my wife to drive to the closest safe point even though the engine warning system said to stop immediately. The engine seems to survive fine. I dont know if you record other data on this type of hose assembly failure, but a redesign with non-plastic clamp might be more durable and more appropriate.

NHTSA ID

11444249

Incident

Nov 27, 2021

MY WIFE AND I WERE DRIVING FROM ARIZONA TO COLORADO. WE WERE TRAVELING AT ABOUT 85 MILES/ HR PASSING ALBUQUERQUE. ALL OF A SUDDEN WE FELT AND HEARD AN EXPLOSION. MY WIFE AND I BOTH DUCKED AND FORTUNATELY I KEPT MY HANDS ON THE WHEEL. WE LOOKED UP AND THE SUNROOF HAD SHATTERED AND BLOWN OUT. THE ONLY THING THAT SAVED US FROM BEING SHOWERED WITH GLASS WAS THE SHADE OF THE SUNROOF WAS CLOSED BECAUSE THE SUNROOF WAS CLOSED AT THE TIME. WE HAD T DRIVE THE REMAINING 400 MILES WITH THE BROKEN SUNROOF. WHEN WE GOT BACK HOME , WE CONTACTED MERCEDES AND ASKED THEM ABOUT THE SUNROOF. THEY BASICALLY DID NOT ACCEPT ANY RESPONSIBILITY FOR ANYTHING EVEN AFTER WE TOLD THEM THAT AFTER GOOGLING ( MERCEDES EXPLODING SUNROOF) A TON OF ITEMS CAME UP INCLUDING SEVERAL LAWSUITS. MERCEDES DOES NOT SEEM TO WANT TO ACCEPT ANY RESPONSIBILITY FOR THE SUNROOF. MY WIFE AND I COULD HAVE BEEN KILLED. WE WERE LUCKY THAT THERE WAS NO CAR AROUND US AND THE FACT THAT I KEPT MY HANDS ON THE STEERING WHEEL. I DO NOT WANT THIS TO HAPPEN TO ANY ONE ELSE BECAUSE THEY MIGHT NOT BE AS FORTUNATE AS US.

NHTSA ID

11402698

Incident

Mar 7, 2021

Mileage

54,000 mi

REAR AXLE LOCK UP BRIEFLY MADE A SOUND LIKE SOMEONE REAR ENDED THE CAR AND SNAP THE LEFT SIDE REAR CV AXLE. VEHICLE IS AWD AND DOES NOT MOVE ON ITS OWN POWER.. SHOP TOW SUV AND ON THE AIR FOUND THE AXLE INNER JOINT JUST SPINS BUT CAR DOES NOT MOVE, THEY PULLED THE AXLE AND THE IS METAL BURNT INTO THE AXLE SHAFT SEEMS REAR DIFF LOCK UP, OIL WAS CLEAN ON THE DIFFERENTIAL.

NHTSA ID

11340655

Incident

Jul 17, 2020

Mileage

105,110 mi

I PURCHASED A 2017 GLS 550 IN JANUARY 2018 FROM LOEBER MOTORS IN LINCOLNWOOD ILLINOIS. THE STICKER ON THE VEHICLE REPRESENTED THAT THERE WERE 'ALL SEASON' TIRES ON THE VEHICLE. AFTER NUMEROUS GUARANTEES FROM THE SALESMEN, I WAS ASSURED THAT THE VEHICLE WOULD BE 'SAFE' ON THE FACTORY TIRES AS THEY WERE REPRESENTED AS ALL SEASON. IT WAS NOT UNTIL I FOUND MYSELF DRIVING THROUGH A SPRING SNOWSTORM IN WISCONSIN THAT I REALIZED THAT THERE WAS SOMETHING TERRIBLY WRONG WITH THE WAY THE VEHICLE WAS HANDLING IN THE STORM. I WAS CONCERNED THAT THE VEHICLE WAS GOING TO END UP ON THE SIDE OF THE ROAD, OR IN A HORRIBLE ACCIDENT, AS THE VEHICLE WAS ALMOST UNABLE TO CONTROL. ALMOST EVERY OTHER CAR ON THE ROAD SEEMED TO BE UNFAZED BY THIS STORM, YET MY $100,000 VEHICLE WAS DRIVING LIKE A ROLLER SKATE.AFTER MUCH RESEARCH, NUMEROUS CONVERSATIONS WITH THE DEALER AND CONTINENTAL TIRES, IT HAS COME TO LIGHT THAT THE TIRES ON ALMOST ALL GLS 550'S ARE ACTUALLY THE CONTINENTAL CROSS CONTACT UHP'S. CONTINENTAL HAS VERBALLY CONFIRMED(ON A RECORDED LINE) AND THROUGH EVERY BIT OF LITERATURE ONLINE, THAT THE TIRES ARE ACTUALLY SUMMER TIRES AND SHOULD NOT BE DRIVEN IN WINTER/SNOW CONDITIONS.WHILE THE TIRES MAY HAVE AN M AND S ON THE SIDEWALL, THIS WAS A DESIGNATION REQUESTED BY MERCEDES TO DEFINE THESE TIRES AS 'ALL SEASON' AS THEY MEET THE TREAD DESIGN FOR THE MINIMUM STANDARDS FOR ALL SEASON. CONTINENTAL HAS STATED THE EXACT OPPOSITE AND DOES NOT EVEN PROVIDE SAFETY DATA FOR THESE TIRES IN WINTER CONDITIONS, AS THEY ARE SPECIFICALLY DESIGNED AS A SUMMER/PERFORMANCE TIRE. THE MISREPRESENTATION ABOUT THIS ISSUE IS OF EPIDEMIC PROPORTION. MERCEDES NEEDS TO TAKE RESPONSIBILITY FOR THIS MISREPRESENTATION AND NOTIFY/RECALLS THE UNSAFE TIRES THAT ARE CURRENTLY ON THESE VEHICLES.THIS IS ONE OF THE MOST DISTURBING BREACHES OF DISCLOSURE AND MISREPRESENTATION I HAVE EVER SEEN.

NHTSA ID

11092420

Incident

Mar 7, 2018

Mileage

11,000 mi

I LOWER THE PASSENGER CAR WINDOW WHEN I ENTERED THE CAR IN A VERY HOT DAY AND THE WINDOW GLASS EXPLOTED. I TOOK THE CAR TO THE DEALER AND THEY SAID IT WAS NOT A CAR DEFECT. HOWEVER, THE CAR WINDOW GLASS JUST EXPLOTED JUST BY LOWERING IT.

NHTSA ID

10970780

Incident

Apr 2, 2017

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).

Complaint Creaking noise, in irregular sequence when driving slowly in combination with slight steering movements and/or Creaking/crackling noises from the area of the wheel bearing on the front axle when cornering/ maneuvering. Sound file attached for comparison. MUST match noise for proper diagnosis. NOTE: Steering functionality is not affected. Cause Contact area between wheel bearing and steering knuckle. See also: LI35.30-P-058566 (Throttle Lift-Off Noise - Rear) LI33.30-P-056665 (Throttle Lift-Off Noise - Front) LI40.10-P-059248 (Wheel cracking noise when cornering) Remedy 1. Perform Operation A and evaluate by testing vehicle. 2. If noise is still present after re-testing: • If 192/232 chassis, verify FIN is in the listed range below in "Operation B" and perform. • If not 192/232 chassis or vehicle is a 192/232 not in the listed FIN range, additional verifications of where the noise is coming from are needed. Use multiple channel NVH method to narrow down location. Verify the LI's listed above were completed or if there are other similar noises associated with the chassis (Example: 192/232 also has under panel noises and an associated LI). Operation A: 1. Clean contact surfaces of wheel bearing and steering knuckle with brake cleaner as seen in the attached pictures. NOTE: The front area of the wheel bearing and the seals must not come into contact with the cleaner, otherwise, the sealing rings will be damaged. 2. Clean threads of wheel bearing mounting. 3. Thinly coat contact surfaces of wheel bearing, steering knuckle, and axle mating face with Molykote (annular joint grease). See the attached steering knuckle and wheel hub pictures for reference. NOTE: Axle mating face greasing is also covered in LI35.30-P-058566 and LI33.30-P-056665. Operation B (Only applies to 192 and 232 in listed FIN range): Only affects vehicles up to FIN end number: • Model series 192: xxx xxx xx 002 876 • Model series 232: xxx xxx xx 022 312 1. Replace steering knuckle. 2. Wheel bearings do not need to be replaced.

Complaint Creaking noise, in irregular sequence when driving slowly in combination with slight steering movements and/or Creaking/crackling noises from the area of the wheel bearing on the front axle when cornering/ maneuvering. Sound file attached for comparison. MUST match noise for proper diagnosis. NOTE: Steering functionality is not affected. Cause Contact area between wheel bearing and steering knuckle. See also: LI35.30-P-058566 (Throttle Lift-Off Noise - Rear) LI33.30-P-056665 (Throttle Lift-Off Noise - Front) LI40.10-P-059248 (Wheel cracking noise when cornering) Remedy 1. Perform Operation A and evaluate by testing vehicle. 2. If noise is still present after re-testing: • If 192/232 chassis, verify FIN is in the listed range below in "Operation B" and perform. • If not 192/232 chassis or vehicle is a 192/232 not in the listed FIN range, additional verifications of where the noise is coming from are needed. Use multiple channel NVH method to narrow down location. Verify the LI's listed above were completed or if there are other similar noises associated with the chassis (Example: 192/232 also has under panel noises and an associated LI). Operation A: 1. Clean contact surfaces of wheel bearing and steering knuckle with brake cleaner (see areas marked blue in pictures "2.jpg" and "3.jpg"). NOTE: The front area of the wheel bearing and the seals must not come into contact with the cleaner, otherwise, the sealing rings will be damaged. 2. Clean threads of wheel bearing mounting. 3. Thinly coat contact surfaces of wheel bearing, steering knuckle, and axle mating face with Molykote (annular joint grease) (see areas marked blue in pictures "2.jpg" and "3.jpg"). NOTE: Axle mating face greasing is also covered in LI35.30-P-058566 and LI33.30-P-056665. Operation B (Only applies to 192 and 232 in listed FIN range): Only affects vehicles up to FIN end number: • Model series 192: xxx xxx xx 002 876 • Model series 232: xxx xxx xx 022 312 1. Replace steering knuckle. 2. Wheel bearings do not need to be replaced.

Complaint After successful commissioning of the HERMES control unit (N112/9) with XENTRY Diagnosis DVD 03/2026, the message "SOS - service not activated" appears on the instrument cluster. In addition, the following two conditions are also met: • HERMES (N112/9) control unit: event code B15CE00 is ACTIVE and STORED (A+S) • Vehicle Documentation System: For the HERMES control unit, the EID1, EID2, ICCID, IMEI, IMSI, TELNR fields in the "Identification/Serial number" column have the value "-" Cause Still under analysis Remedy Recommission the HERMES control unit (N112/9) with XENTRY Diagnosis 03/2026 and add-on 33399 installed or carry out the procedure with a newer version of XENTRY Diagnosis: XENTRY→ "N112/9 - Control unit for telematics services (HERMES)" -> "Adaptations" -> "Control unit commissioning" -> "Commissioning of previously installed control unit"

Complaint The customer requests deactivation of the N112/9 HERMES communication module Note: Deactivation of the HERMES control unit (N112/9) is not supported for gray-market vehicles. Cause Before deactivating the HERMES control unit (N112/9), it must be clarified by the legal department of the respective MPC whether and under what conditions deactivation may be carried out. If deactivation is not permissible under applicable law, the HERMES control unit (N112/9) must not be deactivated. Remedy Please inform the customer that, following deactivation, the vehicle will no longer be able to place an automatic emergency call, nor will the customer be able to place a manual emergency call. After deactivation, the Mercedes-Benz Digital Extras will also no longer be available. Please have the attached sample form checked by your market's legal department, adapted to local requirements if necessary, and approved. Furthermore, after informing the customer about the effects of deactivation, please have the workshop complete and sign the approved form together with the customer, and send it to the MPC via a TIPS case for audit-compliant documentation. Furthermore, the workshop must affix a sticker to the emergency call button cover on the overhead control panel and to the emergency call button itself. After affixing, pictures of the overhead control panel need to be attached to the TIPS case for audit-proof documentation. After deactivation, the HERMES control unit (N112/9) is in the "Out of Service" operating status, and the display "SOS NOT READY" appears in the Audio/COMAND system. This display message tells the customer that the emergency call function is not available. In detail, the following steps must be carried out 1. The workshop must inform the customer about the effects of deactivation (see above) 2. Legal review by the MPC Legal department to determine whether deactivation is permissible for the vehicle and provision of a market-specific customer form based on the examples (see "Example - Deactivation communication module HERMES customer declaration English V3.0.pdf") 3. Completion of the market-specific customer form by the workshop and obtaining the customer’s signature 4. Creation of a XSS ticket by the workshop for the MPC with the signed customer form attached 5. Written confirmation of legally reviewed and approved deactivation by the MPC in the TIPS case (see attachment How+to+request+adding+Code+09o+via+XSS+v2.pdf, point 1) 6. Creation of an XSS ticket for documentation of the SA code "09o" (zero nine oh) in the Vehicle Documentation System (see attachment How+to+request+adding+Code+09o+via+XSS+v2.pdf, steps 2–7) 7. Ordering of stickers (part number A9078172900), quantity: 2 8. Affixing of the sticker (part number A9078172900) to the cover of the emergency call button on the overhead control panel (see attachment HERMES-Deactivation_+pictures+of+sticker.png) 9. Affixing of the sticker (part number A9078172900) to the emergency call button on the overhead control panel (see attachment HERMES-Deactivation_+pictures+of+sticker.png) 10. Taking photos of the applied stickers and attaching them to the TIPS case 11. After the XSS ticket has been successfully processed, the communication module must be deactivated using XENTRY: • Connect XENTRY Diagnosis • Access the HERMES control unit (N112/9) • "Adaptation" tab, menu item "Teach-in processes" -> "Deactivation" • Follow the instructions

Dear Mercedes-Benz USA Dealers, 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 11, 2026. After June 11th, 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.