Total Complaints
36 filings
MERCEDES-BENZ SLK350 · model year
36 NHTSA complaints, 5 crash reports for this specific cohort.
NHTSA overall rating
Not crash-tested
New Car Assessment Program
The 2005MERCEDES-BENZSLK350 carries 36 consumer safety complaints in NHTSA's Office of Defects Investigation database for this specific model-year cohort. Within that volume, owners reported 5 crashes, 3 fires, 11 injuries, and 0 fatalities. No NCAP 5-star crash-test rating is available for this model year in the federal database.
Component-level analysis is where model-year complaints become actionable: the top complaint category for the 2005 SLK350 is unknown or other with 6 filings, followed by service brakes (5) and suspension (5). Concentration in one or two component groups is the classic signature of a systemic defect; a flat distribution usually reflects normal aging, warranty complaints, or isolated build-plant variability.
NHTSA currently has 15 investigation files overlapping the 2005 SLK350. Owners comparing this cohort against neighboring years should pair the counters above with the complaint-by-year trend on the parent model page — a spike in a single year often tracks to a platform refresh, a new transmission supplier, or an updated ECU calibration. Use the related-complaint feed below to read raw owner narratives before deciding whether any pattern here affects your specific use case.
Total Complaints
36 filings
Crashes Reported
5 reports
Source
NHTSA ODI
Federal complaints database
At or below the fleet median complaint volume.
| Component | Count |
|---|---|
| UNKNOWN OR OTHER | 6 |
| SERVICE BRAKES | 5 |
| SUSPENSION | 5 |
| POWER TRAIN | 4 |
| ENGINE AND ENGINE COOLING | 2 |
| ELECTRICAL SYSTEM | 2 |
| ENGINE | 2 |
| FUEL/PROPULSION SYSTEM | 2 |
| POWER TRAIN:MANUAL TRANSMISSION | 1 |
| POWER TRAIN:AUTOMATIC TRANSMISSION | 1 |
| FUEL SYSTEM, GASOLINE | 1 |
| VEHICLE SPEED CONTROL | 1 |
| STEERING | 1 |
| EXTERIOR LIGHTING | 1 |
| STRUCTURE:BODY | 1 |
The contact owns a 2005 Mercedes-Benz SLK-350. The contact stated that while driving at an undisclosed speed, the brake pedal was depressed; however, the vehicle failed to stop as intended. The contact stated that the vehicle eventually came to a rolling stop on the side of the road. In addition, the parking brake was activated; however, but failed to activate as intended. The contact stated that the low brake fluid warning light was illuminated. The contact refilled the brake fluid reservoir. The contact stated that the vehicle was almost involved in two crashes because of the failure. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The dealer was made aware of the failure; however, the contact was informed that the repair was not covered under warranty. In addition, the contact stated that the vehicle was serviced a year prior for an extended warranty repair to prevent suspension corrosion. The contact stated that the dealer advised the contact not to
Mileage: 171,000
The brake lines are rusted from the rear sub Frame that was rusted And caused an accident. They told me the sub frame was the only item covered but that they could only bolt it and not weld if and then the exhaust and brake lines (rusted too bad to describe) werenât covered and since I couldnât afford it they only repaired the subframe and left the rest hanging ! My brakes failed on the way home. No one was injured but I canât believe they let me go home with that condition!
The brake lines are rusted from the rear sub Frame that was rusted And caused an accident. They told me the sub frame was the only item covered but that they could only bolt it and not weld if and then the exhaust and brake lines (rusted too bad to describe) werenât covered and since I couldnât afford it they only repaired the subframe and left the rest hanging ! My brakes failed on the way home. No one was injured but I canât believe they let me go home with that condition!
The brake lines are rusted from the rear sub Frame that was rusted And caused an accident. They told me the sub frame was the only item covered but that they could only bolt it and not weld if and then the exhaust and brake lines (rusted too bad to describe) werenât covered and since I couldnât afford it they only repaired the subframe and left the rest hanging ! My brakes failed on the way home. No one was injured but I canât believe they let me go home with that condition!
the conductor plate along with its speed sensor is faulty. Luckily I just exit the highway, the transmission just stopped working, can't drive forward or reverse and when I apply gas on either D or R, just the RPM speed up as if the car is in neutral. I was stranded on the middle of the road. this happened a few time. after turning off the car and turn it back on usually reset it for a little bit. the first time, I have to replace the transmission.
transmission lines popping off popped off at 60 miles per hour tensed me up it stared smoking pushed the safety hazzard lights on and was able to limp it off the highway its happened 3 times after i repaired them afraid to even drive it now.no no no
transmission lines popping off popped off at 60 miles per hour tensed me up it stared smoking pushed the safety hazzard lights on and was able to limp it off the highway its happened 3 times after i repaired them afraid to even drive it now.no no no
As i was driving (on a bridge) the convertible top/roof gushed and dumped an incredible amount of hydraulic fluid/oil right in my face unexpectedly! This came out of the blue. I had just raised it since it began to rain. The combination of raining weather and being on a one lane bridge and then having that spew into my face rendered me unable to see and had Me swerving almost off the bridge as the other lane had vehicles driving. I almost wrecked and was left with highly painful eyes. In truth it could have lead to death without question had I not had a towel in my passenger seat to wipe my face. Iâm now terrified to drive it but have to. Please help, especially if any others are having the same issue, which seems to be the case. I could have had an accident or worse had an accident with others and off of the bridge!
As i was driving (on a bridge) the convertible top/roof gushed and dumped an incredible amount of hydraulic fluid/oil right in my face unexpectedly! This came out of the blue. I had just raised it since it began to rain. The combination of raining weather and being on a one lane bridge and then having that spew into my face rendered me unable to see and had Me swerving almost off the bridge as the other lane had vehicles driving. I almost wrecked and was left with highly painful eyes. In truth it could have lead to death without question had I not had a towel in my passenger seat to wipe my face. Iâm now terrified to drive it but have to. Please help, especially if any others are having the same issue, which seems to be the case. I could have had an accident or worse had an accident with others and off of the bridge!
My vehicle has excessive rust issues that Iâm being told by the dealership will compromise my safety. There is currently an extension of warranty for only the subframe in rear, but the rust is extended beyond that and is applied to the components needed to be removed in order to replace the subframe. Such as the exhaust pipe and brake lines as well. All are corroded to a high degree up to and including complete brittle material Disintegration. Exhaust and rear brake line cost make it impossible for me to have the vehicle brought back to safely drivable conditions. I have to get to work daily or my family will not eat or have a roof but at a cost of more than what the car is even worth I have no choice but to choose and compromise my safety and those around me or food and shelter for my family. Please help.
My vehicle has excessive rust issues that Iâm being told by the dealership will compromise my safety. There is currently an extension of warranty for only the subframe in rear, but the rust is extended beyond that and is applied to the components needed to be removed in order to replace the subframe. Such as the exhaust pipe and brake lines as well. All are corroded to a high degree up to and including complete brittle material Disintegration. Exhaust and rear brake line cost make it impossible for me to have the vehicle brought back to safely drivable conditions. I have to get to work daily or my family will not eat or have a roof but at a cost of more than what the car is even worth I have no choice but to choose and compromise my safety and those around me or food and shelter for my family. Please help.
My vehicle has excessive rust issues that Iâm being told by the dealership will compromise my safety. There is currently an extension of warranty for only the subframe in rear, but the rust is extended beyond that and is applied to the components needed to be removed in order to replace the subframe. Such as the exhaust pipe and brake lines as well. All are corroded to a high degree up to and including complete brittle material Disintegration. Exhaust and rear brake line cost make it impossible for me to have the vehicle brought back to safely drivable conditions. I have to get to work daily or my family will not eat or have a roof but at a cost of more than what the car is even worth I have no choice but to choose and compromise my safety and those around me or food and shelter for my family. Please help.
improper heat treatment of the balance shaft spocket causing the balance shaft to worn out resulting in advance timing of the CAM. Mercedes acknowledges it's an known issue but don't cover cost of fixing it. Once ecu detected timing is off, it will stop the transmission from accelerating without any warning. Happened to me on a highway, good thing the car still have some momentum and was able to pull to the shoulder while others cars are coming from behind.
The rear subframe is corroded to the point of about to fall off and subsequently anything that is attached. Mercedes has extended a warranty on the subframe which is excellent, but only the subFrame? What about the touching bits like the bolts and screws among other items that are connected to it. So now because I cannot afford the $5,000.00 needed for the other rusted pieces that are brittle and likely to fall off when the subframe is replaced, then they wonât do it. So I must jeapordize my safety as I have to get to school and work.
A few days after a scheduled service visit at a local Mercedes-Benz (MB) dealer I noticed a creaking sound coming from the rear of my 2005 SLK350 that continued to get louder as time went by. I scheduled another appointment for post-inspection and I received the unfortunate news that corrosion of the subframe had resulted in a critical fracture rendering the vehicle unsafe to drive and that I was actually lucky to have not been involved in an accident from the mechanical failure. It is clear from the undercarriage photos that corrosion was localized to subframe junctions where other areas/parts in the vicinity did not experience debilitating fracture damage. I was surprised that a recently-serviced vehicle was now deemed unsafe to drive and required an entire rear subframe replacement. After some further investigation online (via forums, etc.) this appears to be a prominent issue with the R171 generation of rear subframes where corrosion protection was not applied to the steel subfra
A few days after a scheduled service visit at a local Mercedes-Benz (MB) dealer I noticed a creaking sound coming from the rear of my 2005 SLK350 that continued to get louder as time went by. I scheduled another appointment for post-inspection and I received the unfortunate news that corrosion of the subframe had resulted in a critical fracture rendering the vehicle unsafe to drive and that I was actually lucky to have not been involved in an accident from the mechanical failure. It is clear from the undercarriage photos that corrosion was localized to subframe junctions where other areas/parts in the vicinity did not experience debilitating fracture damage. I was surprised that a recently-serviced vehicle was now deemed unsafe to drive and required an entire rear subframe replacement. After some further investigation online (via forums, etc.) this appears to be a prominent issue with the R171 generation of rear subframes where corrosion protection was not applied to the steel subfra
THE FUEL GAUGE IS WORKING ERRATICALLY. AFTER FILLING UP WITH FUEL, GAUGE SHOWS 3/4 FULL. NEXT MORNING, SHOWS FULL. AFTER DRIVING 25 MILES INTO WORK, FUEL GAUGE SHOW 1/4 FULL. END OF THE DAY, FUEL GAUGE SHOWS 1/2 FULL OR EMPTY. THE READING CAN BE ALMOST ANYWHERE AND IS UNRELIABLE. I HAVE HAD TO RESORT TO TRACKING MILEAGE AND FILLING UP BEFORE RUNNING OUT OF FUEL. THE CAR HAS RUN OUT OF FUEL ON A FEW OCCASIONS CAUSING THE CAR TO LOSE POWER AND SPEED ON A MAJOR HIGHWAY WHICH IS VERY UNSAFE. *TR
Mileage: 76,000
REAR SUBFRAME RUSTING FROM THE INSIDE OUT. DUE TO POOR DESIGN, THERE IS AN ARCH THAT HOLDS WATER IN AND THE WATER CAN'T GET OUT CAUSING IT RUST FROM THE INSIDE OUT. SEARCHING MERCEDES ONLINE FORUMS, THIS SEEMS LIKE A PROBLEM LOTS OF PEOPLE PROBLEM AND MERCEDES DENIES THIS PROBLEM. I HAVEN'T HAD AN ACCIDENT YET, BUT IT SEEMS LIKE IT IF I DON'T REPLACE IT. HTTPS://WWW.SLKWORLD.COM/SEARCH/55011/?Q=SUBFRAME&O=RELEVANCE HTTPS://WWW.GOOGLE.COM/SEARCH?Q=MERCEDES+SUBFRAME+RUST&OQ=MERCEDES+SUBFRAME+RU&AQS=CHROME.1.69I57J0L3.10211J0J7&CLIENT=MS-ANDROID-HUAWEI-REV1&SOURCEID=CHROME-MOBILE&IE=UTF-8 THE FOLLOWING PERSONS CAR WAS FLIPPED WHILE IN THE HIGH WAY. HTTPS://WWW.SLKWORLD.COM/THREADS/REAR-SUBFRAME-R171.553156
REAR SUBFRAME RUSTING FROM THE INSIDE OUT. DUE TO POOR DESIGN, THERE IS AN ARCH THAT HOLDS WATER IN AND THE WATER CAN'T GET OUT CAUSING IT RUST FROM THE INSIDE OUT. SEARCHING MERCEDES ONLINE FORUMS, THIS SEEMS LIKE A PROBLEM LOTS OF PEOPLE PROBLEM AND MERCEDES DENIES THIS PROBLEM. I HAVEN'T HAD AN ACCIDENT YET, BUT IT SEEMS LIKE IT IF I DON'T REPLACE IT. HTTPS://WWW.SLKWORLD.COM/SEARCH/55011/?Q=SUBFRAME&O=RELEVANCE HTTPS://WWW.GOOGLE.COM/SEARCH?Q=MERCEDES+SUBFRAME+RUST&OQ=MERCEDES+SUBFRAME+RU&AQS=CHROME.1.69I57J0L3.10211J0J7&CLIENT=MS-ANDROID-HUAWEI-REV1&SOURCEID=CHROME-MOBILE&IE=UTF-8 THE FOLLOWING PERSONS CAR WAS FLIPPED WHILE IN THE HIGH WAY. HTTPS://WWW.SLKWORLD.COM/THREADS/REAR-SUBFRAME-R171.553156
SIDE MARKER BULBS CONSTANTLY BURNING OUT. PURCHASED CAR IN 2012, AND EVERY ANNUAL INSPECTION NEED TO REPLACE BULBS. BUT AFTER ABOUT TWO WEEKS, THEY BURN OUT AGAIN. WAS TOLD BY MECHANIC WIRING IN LIGHT ASSEMBLY DEFECTIVE. COST TO REPLACE ASSEMBLY ESTIMATED $150 PER SIDE/$300 FOR BOTH - EXCLUDING LABOR. IF ASSEMBLY DEFECTIVE, FEEL I SHOULD NOT ABSORB COST TO REPLACE. AN OBVIOUS MERCEDES DEFECT.
Data as of 2025. Sources: NHTSA Office of Defects Investigation (ODI) complaints database, NHTSA recall campaign API, NHTSA NCAP crash-test ratings, and NHTSA FARS for fatality cross-reference.
Read our methodology — how this data is sourced, computed, and verified.