Most common 2004 Mercedes-Benz SL500 problems
Share of the 45 complaints; one complaint can involve more than one system. "~" is the median mileage when the problem started.
Mercedes-Benz SL500 complaints by model year
Best SL500 years: 1995, 1998, 1996. Years to avoid: 2003. Compare all years →
NHTSA defect investigations
Federal safety investigators have looked into a possible defect involving the 2004 Mercedes-Benz SL500:
Air suspension system failure
The subject s-class vehicles contain a compressed air suspension system that uses air struts on each of the four wheels in lieu of traditional springs and shock absorbers.these air struts use compressed air to support the weight of the vehicle and control ride height.in the event of the loss of air from the system, an alert will flash on the instrument cluster warning the driver to either drive carefully or to stop…
What 2004 Mercedes-Benz SL500 owners say
Suspension all 21 →
I submitted via fax earlier this week a formal letter to mr. Exler the president & ceo of mbusa and, cc'd mr. King of the NHTSA that included information about known critical safety issued these vehicles had prior to mbusa importing them to the united states. Mbusa failed to disclose these known issues and, chose to importation these vehicles violating vehicle importation rules. Yesterday-January 31, 2019 I received a call from a representative of mbusa stating he was calling on behalf of mr. Exlers office concerning my letter. I will not be intimidated by mbusa while seeking the truth on why mbusa allowed these vehicles to enter the USA knowing these critical safety issues existed while misleading consumers and, the NHTSA. On January 21, 2019 my vehicle had what is described by mbusa as a catastrophic failure when the entire brake system failed. …
Addendum info to original complaint #10308437 shows that mb service advisor j. Steach advised m .b. Not responsible as driver should "miss" potholes. Engineering analysis shows that it is not possible for driver to steer around potholes. At 70mph mb SL500 travels 103 ft/sec and it is not possible to observe the pothole hazard and categorize as safety risk at speeds of 70mph(103ft/sec) react physiologically and actuate steering system -all in less than one second-one half second each for human response and same for mechanical actuation-insufficient time to avoid pot hole hit. Dark or low light conditions render pothole miss impossible. In any case, the improperly engineered soft low strength alloy wheel design leads any prudent vehicle driver into a crash trap. Wheel,tire, suspension damage evident-needs corrected immediately at expense of mercedez-Benz.. …
Brakes
The contact owns a 2004 Mercedes-Benz SL500. The contact stated that after starting the vehicle, the message "Brakes Reached Historic Threshold" was displayed, which indicated that the brake control unit had malfunctioned. Additionally, while depressing the brake pedal, the brake pedal was spongy, causing the stopping distance to become extended. The vehicle was taken to the local dealer and was diagnosed with brake control unit failure. The contact was informed that the brake control unit needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure, but no assistance was provided. The contact stated that a 25-year warranty for the failure was previously issued by the manufacturer that was associated with the failure, but was not honored. The failure mileage was 62,800.
Question 1: The Sensotronic Brake Control (SBC) unit, which is a high-pressure "brake-by-wire" hydraulic system. Component A7/3. The component is currently installed in the vehicle and is available for inspection. Question 2: The vehicle experienced a sudden, catastrophic loss of hydraulic brake pressure while in operation. This failure required extreme physical force on the pedal and significant increase in stopping distance. The vehicle is currently in my garage with chocked wheels until I figure out what's next. A couple days ago, I had the car at a dealer and requested a review of this system and they released the car back to me stating the system status was, "OK" despite me stating to the dealer that the safety-monitoring counter was found to be at 0 on a 63,000-mile car. …
Fuel & propulsion system
On July 22, 2020 the vehicle (2004 Mercedes-Benz SL500 (r230)began making a loud banging noise in the rear when stopping and turning. I delivered the vehicle to a local shop where the vehicle was diagnosed as having a broken baffle in the fuel tank. The only solution is to replace the entire fuel tank. Many other owners of this model have experienced the same issue and is clearly a manufacturer defect; this cannot be caused by excess wear on the vehicle. Because there is now a large section of the fuel tank freely swinging inside, there is a chance that this could cause a spark and subsequent explosion. I cannot safely drive this vehicle until the fuel tank is replaced at a very large cost. This model should have been recalled when this issue was first coming to light over 15 years ago.
Tl* the contact owns a 2004 Mercedes-Benz SL500. When the vehicle was started, the contact heard an abnormal knocking sound underneath the vehicle near the fuel tank. Additionally, there was a constant fuel odor inside the vehicle. The vehicle was taken to Mercedes-Benz of virginia beach (located at 4949 virginia beach blvd, virginia beach, va 23462, [phone]) where it was diagnosed that one of the baffles in the fuel tank fractured, separated, and needed to be replaced. The vehicle was not repaired. The manufacturer was not notified. The approximate failure mileage was 144,000. The VIN was not available.
2004 Mercedes-Benz SL500 engines & fuel economy
| Engine | Transmission | Drive | MPG city / hwy / combined |
|---|---|---|---|
| 5.0L 8-cyl | 7-speed automatic | RWD | 14 / 21 / 17 |
EPA ratings. Class: Sports car.
Frequently asked questions
Is the 2004 Mercedes-Benz SL500 a good car?
Based on 45 owner complaints filed with NHTSA, the 2004 SL500 rates average: 1.9× as many complaints as a typical year of the SL500 at the same age. Complaint counts don't account for sales volume or individual maintenance, so have any used car inspected before buying.
What is the most common problem with the 2004 Mercedes-Benz SL500?
The suspension — 21 complaints, 47% of all complaints for this model year, most often about front. Next are the brakes (11) and fuel & propulsion system (9).
How many recalls does the 2004 Mercedes-Benz SL500 have?
NHTSA lists no recalls for the 2004 Mercedes-Benz SL500. You can still confirm with your VIN using our VIN recall check.
What are the best and worst years of the Mercedes-Benz SL500?
The best years by complaints, compared at the same age, are 1995, 1998 and 1996. Years to avoid or approach with caution: 2003. See the full Mercedes-Benz SL500 years comparison.
At what mileage do 2004 Mercedes-Benz SL500 problems happen?
The median mileage reported in complaints is about 76,000 miles; 25% of problems with a recorded mileage started before 50,000 miles.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.