2015 Mercedes-Benz GL550

On 8/5/2026, the power boost on the vehicle was lost while at a nearby shopping center. Braking became very difficult and it was dangerous to drive even a little distance. There were no warning lights from the vehicle. We had it towed to an independent repair shop where they determined the brake booster had failed. They did a recall check and saw that it didn't apply to our specific vehicle. They repaired it which cost $2500. Later, we did research and found that there is an expanded recall, 22V315000, which includes our year, make, and model! Our vehicle brake booster failed in the same manner as expressed in that recall. I still have the failed brake booster itself. We'd like you to have Mercedes expand the recall to include our vehicle as well as those with similarly sourced brake boosters. I called Mercedes customer service and they simply confirmed that our vehicle wasn't covered by the recall but to contact NHTSA to file a complaint to start the inclusion process.

NHTSA ID

11762852

Incident

Aug 5, 2026

See attached document for complaint.

NHTSA ID

11730215

Incident

Feb 10, 2026

See attached document for complaint

NHTSA ID

11583052

Incident

Feb 15, 2024

My 2015 GL550 has 90k miles on it and is city driven, on 09/11/2023 when I was trying to pull out onto a main rd my suv hesitated and the check engine light came on, luckily traffic wasn’t heavy at the time so I wasn’t in any accidents. I called and was able to get my suv into my local Mercedes dealership for an inspection. When the suv was dropped off the check engine light had gone off but when the service center pulled up the codes it showed both turbos were bad and have to be replaced. This isn’t something that should happen to a vehicle that is regularly serviced only at Mercedes service centers, isn’t 10years old yet, never wrecked, and has less then 100k miles on it. If this had happened with heavy traffic or any other situation it could have caused a serious wreck. My suv is currently at the dealership having both turbochargers replaced at a cost of $12,000 out of pocket. I feel that Mercedes needs to look into the turbochargers used in their vehicles.

NHTSA ID

11546616

Incident

Sep 11, 2023

Upon receipt of vehicle, when the weather was nice, a rattle in the engine compartment appeared to take place intermittently. Upon diagnosis by a dealership, intermittent was confirmed to take place on a cold start, and not intermittently. Upon further research, it was found the rattle is related to a manufacturer's defect with the timing chain tensioner(s) and their interaction with the valves. My safety was put at risk substantially. I live in the cold upper midwest. Every start of the vehicle is a cold start, and if I risk damaging my engine at any given hour, during the dead of winter, with little to no available funds, I am at risk of hypothermia, starvation, even death. The problem, as noted in paragraph one has been reproduced by a dealer. The vehicle has not been inspected by the manufacturer in full, but the issue is known by Daimler since 2013 for certain. No warning lamps or messages are associated with the issue. The only symptom is the rattle in the engine compartment, and when appropriate tension with the timing chain is obtained, the rattle immediately goes away.

NHTSA ID

11508624

Incident

Jan 1, 2015

There are many models of the gl550 ranging from 2012-2015, where the second row driver side seats get stuck in a downward position. Recently it happened to me and another gl550 was in the shop at Mercedes North Houston for repair for the same issue. These are very common in this make and model and something needs to be addressed concerning the matter.

NHTSA ID

11488454

Incident

Sep 7, 2022

As I was driving down the freeway the whole vehicle caught on fire and we got out of the car and within 2-3 minutes while car was burned to ashes.

NHTSA ID

11470389

Incident

Jun 16, 2022

MY CAR HAS AN ONGOING PROBLEM WITH THE HVAC SYSTEM. IT GENERATES A MOLD AND MILDEW SMELL WHILE USING THE AC AND HEAT. MERCEDES SAYS THEY NO OF THIS ISSUE BUT HAVE NO PERMANENT FIX. THE SMELL IS SO BAD THAT IT IS ALMOST UN-DRIVABLE. MERCEDES DEALERSHIPS HAVE BULLETINS THAT DENOTE THE ISSUE IS KNOWN, BUT THEIR WORK AROUND ONLY TEMPORARILY IMPROVES THE SMELL. THERE IS AN OBVIOUS ENGINEERING ISSUE WITH THE HVAC SYSTEM THAT IS UNHEALTHY. THERE IS APPARENTLY THAT FORMS AROUND THE MOLD AROUND THE AC EVAPORATOR. MERCEDES HAS AN INTERNAL ALERT # TSB LI83-30-P-059119. THIS IS NOT A PERMANENT FIX AND ONLY IMPROVED THE SMELL FOR 3-4 WEEKS AND TOOK OVER TWO DAYS TO IMPLEMENT. THE SMELL OCCURS ALL THE TIME WHEN EITHER THE AC OR HEATER IS ON. THIS STARTED AT 2200 MILES AND CONTINUES TODAY (I HAVE 17K MILES NOW).

NHTSA ID

10933757

Incident

Jul 1, 2016

Mileage

2,200 mi

Complaint During part of the steering movement, it feels heavier or more difficult to steer in the same spot every time. OR Rattling, humming, dry sliding/gravel noise from the electric steering system when steering (see attachment). Complaint does not impact the ability to safely steer or control the vehicle. Cause Ball screw drive (KGT) of electric steering damaged by: 1. External force due to: ‑ Hitting the curb/posts with the front wheels. ‑ Driving over obstacles (e.g. pothole/ threshold/ speed bump/ gully) at an inappropriate speed. 2. Corrosion/ water ingress through a damaged boot (see attachment). ‑ Cracks (1) ‑ High pressure cleaner (2) ‑ Animal bite (3) See various examples listed in the attachments for examples of outside influence. Remedy Remove boot clamps closest to steering gear housing on both left and right (as seen in "Steering Rack Boot Clamp Location"). Pull back boot and inspect for rust, broken end stops, water, or any other anomalies. Replace electric steering. Note: Steering gears replaced due to outside influence or damage must not be claimed under warranty!

Complaint A popup is seen on the HU with the message "data connection temporarily not available". Potentially affected functionalities in NTG4.5, NTG5 1.Weather 2.Local Search 3.IP Radio 4.Send2Car 5.Speech Detection Service 6.Navigation 7.iHeartRadio 8.Traffic Cams Cause MB Apps is sundowned for all vehicles with NTG4.5 and NTG5 Head Unit Variant. Remedy No support available for NTG4.5 and NTG5 Head Unit Variants for MB App related topics. Note: Please do not create TIPS. Please do not replace any components. HU/Hermes SW update / SCN coding will not fix the issue.

Complaint Clanking noise from the area of the speakers in the doors. Cause Under analysis. Remedy To narrow down the cause, first of all remove the door trim. • If the noise continues to occur even with the door trim removed, then continue the diagnosis working towards the speaker and if necessary, create a TIPS case with an informative video as an attachment. Information: Please refer to this document in the warranty claim and, after completing diagnosis, select the damage code corresponding to the component part that caused the problem. • If the noise stops when the door trim is removed, please proceed in accordance with LI72.10-P-067691. Information: In this case, do not use a damage code for the speakers in the warranty claim!

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.