2014 Mercedes-Benz GL450 Problems
Owner-reported complaints filed with NHTSA, grouped by component
Data refreshed
What this page shows
Everything below is an owner-reported complaint submitted to NHTSA about the 2014 Mercedes-Benz GL450, grouped by the component NHTSA recorded on the report. These are not confirmed defects, and they are not recalls. NHTSA does not verify most reports before publishing them, and a category with more reports in it is not evidence that a part is defective.
Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.
Reports by component
Ranked by how many owner reports name each component category
- Engine729.2%
- Electrical312.5%
- Visibility312.5%
- Interior & seats28.3%
- Brakes28.3%
- Powertrain (other)28.3%
- Exterior lighting14.2%
- Other / unspecified14.2%
- Driver assistance14.2%
- Suspension14.2%
- Body & structure14.2%
Percentages are of component mentions. A single complaint can name more than one component, so these do not sum to the total complaint count.
Each component in detail
What the reports in each category say, in the owners' own words
Engine
Reports naming the engine itself — including stalling, misfires, oil consumption, cooling and internal engine components.
From owner reports, verbatim
There were numerous Engine Oil Leak Recalls by Mercedes-Benz. There was a recent recalls announced in 2023, however, my vehicle 2014 GL450 with now about 50K miles, was not included in the list. Since there have been engine oil leaks problem reported and recalls, I'd like to report my car engine oil leaks problem too. It seems that the engine oil leaks problem is a "design" issue and across many car models and years made by Mercedes-Benz. With that said, it make safety sense to have the recalls extended to those cars with engine oil leaks problem reported. Below is information from dealer diagnostic report on engine oil leaks problem, "Valve Cover Re-seal: FRONT TIMING COVERS RECOMMENDED RESEAL SIPING OIL BOTH SIDES Item Description During a vale cover reseal, the valve cover is scraped and cleaned of any old residue, before a layer of silicone sealant is applied to the cover and then reattached to the head of the engine. Reason If not resealed or replaced, the valve cover will leak oil resulting in a burning smell coming from the vehicle’s engine. A loss of oil over time can result in harmful damage of the engine's internal components."
On this Engine 166 model, I experience noise when Idling and when driving, coming from Engine with no code to indicate what is the problem of the car. This create the heat of the Engine to go up than normal and make the fan to run at high speed. When I call dealer, they told me its common problem on these Engine 166, and I need new Engine. I wanted to get second opinion from different Dealership and I got same answer, its common problems and I need new Engine or to Rebuild. I went online and I ask few people with same car Make, model and year, and the have same problems. My concern is only Dealer knows what is the issue but they don't want to inform Consumer what is the problem, instead they tell Consumer to replace the Engine, We don't how bad it is for safety. The problems it cannot be diagnosed because it doesn't produce any codes to indicate the problem. The noise continue until you turn off the Engine
Too few reports in this category for a page of its own — they appear in the full complaint list.
Electrical
Reports naming the electrical system — wiring, battery, charging, control modules, infotainment and electrical accessories.
From owner reports, verbatim
Our vehicles computerized self-diagnostic system (OBD) registered faults.
Oil leaking and wicking into camshaft position sensors, camshaft magnets, O2 sensors, engine wiring harness and ultimately, the ECU is destroying all electronic components connected to the engine causing misfiring and seizing. The issue is quite prevalent via internet research as potentially thousands of owners all experience the same issue. Our local Mercedes Benz dealer indicated this issue "just popped up" immediately outside the warranty period (1 yr) for our used purchase, and would require a replacement of the camshaft, sensors, magnets, and wiring harness to the tune of $14,000. This is a design flaw of the engine that placed these components in locations predisposed to contact with engine oil. The root cause of the oil leak is unknown and even Mercedes Benz can not tell why the oil is leaking on these components. If this issue is so prevalent with thousands of owners with the GL450's, as evidenced by internet searches via Mercedes Benz fan sites, why has no service bulletin or recall been instituted? The overall issue is starting to cause issues with the safety features of the vehicle as well, with alerts (driveline assist, etc) either misfiring or not going off at all.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Visibility
Reports naming windshields, glass, wipers, defrosters and mirrors.
From owner reports, verbatim
After picking up children from school, I was driving out of the parking lot down a slow-speed arterial road (35 mph posted speed limit). Roughly 30 seconds after reaching the posted speed limit we heard a loud bang (like a gunshot) and immediately pulled over. The middle section of the panoramic sunroof had shattered. Upon examination on the side of the road there was no apparent impact spot or item in the roadway that would have indicated that particular section of the roof had been struck by anything (no rock, branch, brick, etc), nor were there any other vehicles in the vicinity that might have kicked up an object to hit the roof and nothing else. The sunroof appears to have spontaneously shattered without warning. The temperature outside was moderate (roughly 60 degrees) and the car had been driven earlier in the day without incident. A police report was filed for potential vandalism and I'm currently waiting for the insurance company to contact me to discuss and inspect.
TL* THE CONTACT OWNS A 2014 MERCEDES-BENZ GL450. WHILE OPERATING THE VEHICLE, SEVERAL MESSAGES DISPLAYED REGARDING THE PARKING BRAKE RELEASE, TRANSMISSION, AND THE VEHICLE BEING INOPERABLE. ALSO, SEVERAL ELECTRICAL FEATURES MALFUNCTIONED. THE VEHICLE WAS TOWED TO WORLD WIDE MOTORS INC. (3900 EAST 96TH ST, INDIANAPOLIS, IN) WHERE IT WAS DIAGNOSED THAT THE MAIN VEHICLE WIRE HARNESS WAS DAMAGED DUE TO WATER THAT DRAINED FROM THE SUN ROOF INTO THE PANELS OF THE VEHICLE. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE. THE FAILURE MILEAGE WAS 57,000.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Interior & seats
Reports naming seats, latches, locks, linkages and interior fittings.
From owner reports, verbatim
The contact owns a 2014 Mercedes-Benz GL450. The contact stated while the vehicle was stationary, she noticed moisture inside the vehicle. The contact stated that the vehicle filled up with water while it was raining. The contact took the vehicle to an independent mechanic, who stated that the rear hatch was faulty and allowed water to enter the vehicle, but no leaks were found. The independent mechanic had to replace the rubber casing on the rear door hatch, the electrical wiring, and replace the floor carpet. The vehicle was repaired. The contact called the local dealer and made them aware of the failure. The manufacturer had not been informed of the failure. The failure mileage was 124,315.
TO THE BEST OF MY KNOWLEDGE - CERTAIN HIGH END GL MODEL HAVE OPTIONAL EASY THIRD ROW ENTRY. THE SECOND ROW IN SUCH MODELS FOLDS WITH A TOUCH OF A BUTTON. HOWEVER WHEN FULLY DEPLOYED - THE SECOND ROW SEAT'S HEAD REST IN SUCH MODELS PREVENT PROPER INSTALLATION OF KID'S CARSEAT ' SUCH THAT THE UPPER PART OF THE CARSEAT IS PROJECTED FORWARD. I AM 6 FEET AND CAN EASILY PUT THE WHOLE OF MY FORARM BEHIND MY KID'S CARSEAT AFTER INSTALLATION. THE RESULT IS ' A VERY UNCOMFORTABLE FORWARD POSITIONING OF THE KID'S CARSEAT. MY KID HAS REPORTED NECK SPRAIN MULTIPLE TIMES. THE ISSUE DOES NOT RESOLVE WITH USING A BOOSTER ONLY (WITHOUT BACKREST) OR WITH CAR'S HEADREST NOT DEPLOYED ' AS IN ALL SITUATIONS THE CAR'S HEAD REST STILL PUSHES MY KID'S HEAD FORWARD. I BELIEVE THAT IT'S A POTENTIAL SAFETY ISSUE AS WELL. THIS ISSUE HAS BEEN WIDELY REPORTED ONLINE. I GUESS MERCEDES TOOK NOTE OF IT AND AS PER THE LOCAL DEALER - THEY HAVE FIXED IT IN THE NEWER MODELS (2016 ONWARDS). IN ORDER TO FIX MINE - MY FIRST PLAN WAS TO REMOVE THE SECOND ROW HEADREST (THE ONE ON WHICH I INSTALL MY KID'S CARSEAT). DEALER TOLD ME THAT IT'S NOT POSSIBLE - AND INSTEAD RECOMMENDED A RETROFIT. QUOTE WAS $1300. GIVEN THAT IT'S PRIMARILY A MANUFACTURING DEFECT I CALLED MERCEDES USA - THEY REPLIED PROMPTLY. BASICALLY ACKNOWLEDGED THAT THERE IS AN ISSUE AND OFFERED ME $350 IN SERVICE CREDIT, BUT EXPECTED ME TO SHELL OUT THE REMAINING $ 950 OUT OF MY POCKET. WHEN I TOLD THEM THAT IT'S UNFAIR TO DO SO ' AS IT'S PRIMARILY A MANUFACTURING DEFECT ' THE AGENT BASICALLY TOLD ME THAT I SHOULD INSTEAD BE HAPPY THAT THERE'S A REMEDY AVAILABLE AND THAT ALSO AT MY LOCAL MERCEDES DEALER. HE TRIED TO USE MY CURRENT MILEAGE (62K) AS A JUSTIFICATION FOR NOT PICKING UP THE COST - EVEN THOUGH THIS HAS NOTHING TO DO WITH MILEAGE AND MY VEHICLE HAS AN UNLIMITED MILEAGE WARRANTY UNTIL 08/2020.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Brakes
Reports naming service brakes, the antilock braking system, brake hoses, master cylinders or the parking brake.
From owner reports, verbatim
There is a recall on some of the make & models of my truck with different years but, my truck has been having the same issue & I believe that myself & my family may be at risk. The recall states that if the oil level in the ACS reservoir is below the minimum level, the oil may foam & leak out of the vent holes in the reservoir cap. The leaking of oil in the presence of ignition source can increase the risk of fire. I have been having to add two quarts of oil to my car every month for almost a year & there has been no oil in my driveway at all. The oil is going somewhere & I would like for my truck to be put on the recall list & have this issue addressed. My brakes also seem to have an unexplainable issue. Most times they're perfect but, sometimes they vibrate very hard when stopping no matter how fast or slow I'm going at the time. When I get them checked, I'm told that they're fine. I read a recall about the brakes as well.
YOU NEED TO ORDER A RECALL OF MERCEDES BENZ GL450 (2014) (VIN [XXX]). I HAD TO TAKE THE VEHICLE FOR REPAIR BECAUSE THE BRAKES WERE LOCKING WHEN I DROVE BACK FROM SAN DIEGO AND SEVERAL TIMES I WAS CLOSE TO HIT OTHER VEHICLES. IN ADDITION, THIS WEEK MY BRAKES STARTED SQUEALING AND I HAD TO WAIT UNTIL FRIDAY (5/8/2015) TO HAVE THE VEHICLE INSPECTED. NOW THEY TELL ME THAT AT 16,000 IT IS NORMAL FOR THIS CAR TO BE COMPLETELY OUT OF BRAKES (WORN OUT) AND THAT THE CALIPER DAMAGED THE ROTORS AND THAT THEY WANT ME TO PAY $700 TO REPLACE THE PADS AND ROTORS BECAUSE THEY DO NOT WANT TO HONOR THE WARRANTY. I TOLD THEM THAT THIS CAR WAS FULLY SERVICED A COUPLE OF MONTHS AGO AND THEY SHOULD HAVE REPLACED THE BRAKE PADS IF THEY FELT THAT THEY WOULD BE COMPLETELY WORN OUT. I HAVE CHANGED BRAKE PADS MYSELF IN THE PAST AS A HOBBY AND I KNOW VERY WELL BRAKE PADS LAST BETWEEN 35,000 AND 50,000 MILES BEFORE THE CALIPERS HIT THE ROTORS. I THINK THEY DON'T WANT TO ADMIT THAT EITHER THEY REPLACED MY PADS WITH USED ONES OR THAT THE PADS ARE LIKELY TO CRACK AND THEN THE CALIPER DAMAGED THE ROTORS. THIS TYPE OF VEHICLE IS A SHIP ON A HIGHWAY THAT COULD KILL MANY PEOPLE IF THE BRAKE SYSTEM FAILS WHILE DRIVING AT THE SPEED LIMIT. THIS IS A $90,000 CAR AND IS PROVEN TO BE ONE OF THE UNSAFEST VEHICLES ON THE ROAD. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6). *TR
Too few reports in this category for a page of its own — they appear in the full complaint list.
Powertrain (other)
Powertrain reports that are not specifically the engine or transmission — driveshafts, axles, transfer cases and differentials.
From owner reports, verbatim
Oil leaking and wicking into camshaft position sensors, camshaft magnets, O2 sensors, engine wiring harness and ultimately, the ECU is destroying all electronic components connected to the engine causing misfiring and seizing. The issue is quite prevalent via internet research as potentially thousands of owners with my engine (M278) all experience the same issue. Mercedes Benz advises a $11,000 temporary fix by replacing all engine electronic components but the problem will occur again since the root cause of the oil leak is unknown. Be advised that this is NOT a normal wear and tear issue. This is a design flaw of the engine that placed these components in locations predisposed to contact with engine oil. The root cause of the oil leak is unknown and even Mercedes Benz can not tell why the oil is leaking on these components. If this issue is so prevalent with thousands of owners with the M278 engine in the GL450's, as evidenced by internet searches via Mercedes Benz fan sites, why has no service bulletin or recall been instituted? I am sure your agency can discover numerous examples of this same issue by researching service tickets from Mercedes Benz service centers nation wide. An $11,000 fix is not routine maintenance and Mercedes Benz should be made to fix this prevalent issue via a recall or a service bulletin.
TL* THE CONTACT OWNS A 2014 MERCEDES BENZ GL450. THE CONTACT STATED THAT THE TRANSMISSION JERKED AND HESITATED TO SHIFT. THE FAILURE OCCURRED NUMEROUS TIMES. THE VEHICLE WAS TAKEN TO THE DEALER SEVERAL TIMES. THE TECHNICIAN REPROGRAMMED THE TRANSMISSION SOFTWARE AND THE MODULE WAS REPLACED; HOWEVER, THE FAILURE PERSISTED. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE WAS 30.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Exterior lighting
Reports naming headlights, tail lights, turn signals and other exterior lighting.
From owner reports, verbatim
' '['? /The right front headlight was replaced (after receiving a headlight warning) approximately about a year after the warranty expired. The dealership claimed this was due to moisture in the headlight. In August 2021, the left front headlight showed to be having issues with the same error message. Upon further inspection, the mechanic noticed that it was not moisture in the headlight that was causing the short, but an oily substance. The mechanic believes that there might be a bushing in the headlight that might be melting/breaking down due to the heat. This is causing the headlight to short and require a $3500 replacement
Too few reports in this category for a page of its own — they appear in the full complaint list.
Other / unspecified
Reports whose component NHTSA recorded as unknown, or that do not map to one of the categories above.
From owner reports, verbatim
Front drivers side (Front Left) Aluminum wheel rim is cracked and will not hold tire pressure. We loose about 10 psi per day because of it. Now we have to replace this rim at significant cost. However, that's not the main issue. The main issue is whether this is a manufacturing defect that has put our lives at risk since 2014 (bought it brand new) until now in 2023 - over 9 years. The tire dealer Firestone discovered the crack and let us know. Yes, available for inspection. Yes, safety has been put at risk. Yes, confirmed by local Firestone Tire near us. Insurance may inspect it, we are calling them tomorrow as they are closed now. Tire pressure light went on, and has been on for awhile. But who would have thought to inspect rim, it is steel, and should not have cracked. Friends of mine say that it is possibly an OEM defect as Aluminum cast wheels should not do this. This car has never been in a moderate or serious crash. Fender benders sure, but nothing involving the tires.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Driver assistance
Reports naming forward-collision avoidance, lane keeping, back-over prevention, cruise control and related electronic driver-assistance systems.
From owner reports, verbatim
It has makes sound noise and timing chain tension is made very poor not safety , also warming blibd spot frozen not working, display electric poor damage byself tomve fix timing dealer wants 15,000$ to be fix more then value of the suv
Too few reports in this category for a page of its own — they appear in the full complaint list.
Suspension
Reports naming suspension components — springs, struts, shocks, control arms and related hardware.
From owner reports, verbatim
TL* THE CONTACT OWNS A 2014 MERCEDES BENZ GL450. THE CONTACT STATED THAT THE VEHICLE BOUNCED AND PULLED TO THE LEFT AND RIGHT WHILE DRIVING WITH AN UNKNOWN WARNING LIGHT ILLUMINATED. THE VEHICLE WAS TAKEN MERCEDES-BENZ OF CORAL GABLES (300 ALMERIA AVE, CORAL GABLES, FL 33134), AND WAS DIAGNOSED THAT THE FOUR-WHEEL SUSPENSION NEEDED TO BE REPLACED. THE VEHICLE WAS REPAIRED. THE CONTACT STATED THAT THE FAILURE OCCURRED TWICE. THE FIRST FAILURE WAS REPAIRED AT AN INDEPENDENT MECHANIC. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE BUT, OFFERED NO ASSISTANCE. THE FAILURE MILEAGE WAS APPROXIMATELY 55,000.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Body & structure
Reports naming the vehicle structure, frame, body panels, doors, hood and trim.
From owner reports, verbatim
TL* THE CONTACT OWNS A 2014 MERCEDES-BENZ GL450. WHILE OPERATING THE VEHICLE, SEVERAL MESSAGES DISPLAYED REGARDING THE PARKING BRAKE RELEASE, TRANSMISSION, AND THE VEHICLE BEING INOPERABLE. ALSO, SEVERAL ELECTRICAL FEATURES MALFUNCTIONED. THE VEHICLE WAS TOWED TO WORLD WIDE MOTORS INC. (3900 EAST 96TH ST, INDIANAPOLIS, IN) WHERE IT WAS DIAGNOSED THAT THE MAIN VEHICLE WIRE HARNESS WAS DAMAGED DUE TO WATER THAT DRAINED FROM THE SUN ROOF INTO THE PANELS OF THE VEHICLE. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE. THE FAILURE MILEAGE WAS 57,000.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.
Elsewhere on this vehicle
Data sources
- NHTSA Office of Defects Investigation — owner-reported complaints and the components recorded on them
Data on this page last refreshed .