Common Mercedes SL500 Suspension Problems

Common Mercedes SL500 Suspension Problems

Troy Hammond
9 minute read


You may notice that your Mercedes SL500 is leaning slightly to one side or riding too low. Perhaps you already see the dreaded Active Body Control (ABC) system warning light illuminated. Whatever the problem, your Mercedes SL500 hydraulic suspension is likely failing. The question you might be asking now is, "Why?" While hydraulic suspension offers outstanding responsiveness and comfort, there are certain drawbacks. 

The most notable pitfall is the all-but-guaranteed eventual failure of the system leads to the potentially costly expense of repairing and replacing it. To help determine whether your system is failing or needs repairs or replacement, you should know what symptoms to look out for, what causes SL500 suspension problems and your available repair options.

Common Signs and Symptoms of Mercedes SL500 Suspension Problems

Common Signs and Symptoms of Mercedes SL500 Suspension Problems

You may notice typical Mercedes SL500 suspension problems while driving, cornering, stopping and even when your car is parked. Here are the symptoms to be aware of:

  • The ride is bouncy: A bouncy ride means poor responsiveness or breakdown, leading to the failure of your suspension. You will feel this most on uneven roads or while corning — the drastic shifting is called rolling — and you may experience nose-diving when you brake.
  • You hear rattles, knocks, whines and hums: With wear, breakdown of parts and failure, you will likely hear peculiar noises from your car's suspension. These noises will worsen if hydraulic fluid is low, parts are cracked, or O-rings, seals, membranes and rubber components disintegrate and are left unchecked.
  • The car sags while parked: If the front of your car squats or you're experiencing Mercedes SL500 rear suspension problems where the back suspension dips lower than the front, you may need new suspension parts. Additionally, the suspension at one wheel may be faulty, meaning the sag is limited to a single corner of the vehicle.
  • ABC Warning or STOP appears on the dashboard: This may permanently display and likely point to the car being too low, flash intermittently or only appear when going over speed bumps or taking sharp corners. Whether intermittent or permanent, visit your nearest auto shop immediately or have the vehicle towed to avoid further potential damage.
  • "Drive Carefully" or "Visit Workshop" light appears: This will likely appear before the STOP warning illuminates though you should still take it seriously. It may only be a minor issue, such as a loose electrical connection, but could just as easily be something serious like an accumulator leaking hydraulic fluid. Drive Carefully means something is not functioning optimally, while Visit Workshop indicates a component has likely failed.
  • Height adjustment features are unresponsive: For instance, the ABC Sport function should allow the driver to adjust the suspension range depending on terrain and driving style, and the self-leveling feature should change the vehicle height depending on cargo level. These features may not function correctly or could be entirely unresponsive.
  • The handling is affected: Your steering and suspension are complementary systems — partly because the SL500 has a tandem pump divided into two sections. If you experience SL500 suspension problems, your steering will feel loose, less responsive and difficult. Although these are also signs of steering rack, alignment or power steering issues, you should have it assessed.
  • There is uneven tire wear: Your tires wearing at different rates may be due to various Mercedes SL500 problems, though a faulty suspension is possible.
  • You notice hydraulic fluid leaking: Your ABC system may leak oil for several reasons, and the leak may originate from different areas of the suspension. The fluid is vital to adjusting the suspension — leaks lead to pressure issues and an overworked pump.

Causes of SL500 Suspension Problems

Causes of SL500 Suspension Problems

It is wise to do routine maintenance and check your car to avoid common Mercedes SL500 suspension problems. Contact a qualified technician to assess your suspension if the warning lights come on or if you suspect suspension problems.

1. The Mercedes Active Body Control (ABC) Is Complex

The Mercedes' branded Active Body Control combines elements of an active suspension to control movement and hydropneumatic suspension system aspects to create its intricate ABC system.

It detects movements using multiple sensors and uses a control module to adjust the suspension. Using hydraulic fluid-filled components, it capitalizes on hydraulic servomechanism technology and hydropneumatic suspension. The combination of these technologies results in an incredibly responsive and adaptive system that creates a seamless ride, though it also means many things can go wrong.

Furthermore, no component acts in isolation when you have a system as complex as the ABC system. Instead, ride height, acceleration, strut extension and directional sensors feed this data to the control module every 10 milliseconds, which then assesses and adjusts fluid. If a single sensor, valve, strut or other part fails, it will affect the entire chain and cause a knock-on effect, potentially damaging further components.

2. SL500 Suspension Parts Are Prone to Wear

Although this system relies less on more traditional mechanical components and instead uses the transfer of hydraulic fluid, several moving parts still experience friction and wear with time. The hydraulic pump includes several moving pieces. The struts — which are responsible for the bulk of the suspension adjustment movement — have many parts that also experience continuous movement.

Many parts can be difficult and expensive to replace. And for any single component, the entire system could fail once it wears out. 

3. ABC Suspension Components Are Fragile

The SL500 uses a series of lines to transport the hydraulic fluid from the pump into the struts. These lines need to be flexible and thus are made of materials like plastic and rubber. And plastic and rubber lines can be easily cut or ripped from road rubble or other debris. Even a small leak or improperly sealed valve will significantly worsen the performance of the suspension. 

A hole in a line will cause the pump to work harder to keep the struts pumped up. This will cause the pump to wear out even faster. This will put extra stress on the other parts of your suspension system. That will lead to the early breakdown of every other component. Because hydraulic fluid leakage is a common problem with potentially catastrophic consequences, fixing or replacing parts quickly is essential once they're damaged or worn.

4. Debris Has Accumulated and Built Up

A buildup of debris over time in the valve block leads to sticking and causes the filter to fail. Dirt and dust can also get inside the struts, causing the seals to break down and causes leaks. Additionally, dirty hydraulic fluid causes abrasion, so the pump bearings wear excessively, and the pump ultimately fails.

Your Mercedes SL500 is at excessive risk if you leave the car standing for prolonged periods, especially without servicing or checking for fluid contamination, which leads to severe damage. 

Repair Options for Mercedes SL500 Suspension Problems

Repair Options for Mercedes SL500 Suspension Problems

You have three primary ways to fix your Mercedes SL500 problems regarding the suspension.

1. Replace the Original Equipment Manufacturer's Suspension

The first and most obvious option is to take it to the dealership or a mechanic. They'll get the OEM parts ordered and replaced. Repairing the entire system could cost you several thousand dollars. For many, that's too much to spend on an aging car.

2. Fit Aftermarket Air Suspension Components 

Another option is to replace your current suspension components with aftermarket hydraulic suspension components, which offer a similar solution to what you are used to.

These are less expensive than the OEM parts, but you still have several problems. Remember, these systems are very complex. That means a mechanic needs to spend a lot of time under the hood to install or repair them. So while you'll save a little money on the parts, the labor bill will still be sky-high. 

3. Install Traditional Coil Springs Using a Conversion Kit

If those massive repair bills don't sound like the way you want to fix your Mercedes SL500 suspension problems, you do have another option. That is to forget that troubled hydraulic suspension entirely and replace it with a sturdy, dependable coilover suspension kit that offers a reliable and cost-effective alternative to hydraulic suspension.

A coilover suspension is a much simpler solution than the hydraulic one. Instead of a complex network of tubes, pumps and computers, your Mercedes SL500 will sit on robust, sturdy stainless steel. And with Strutmasters' patented Glide-Ride technology, you'll enjoy a smooth ride that rivals your SL500's suspension when it was new. 

Shop Strutmasters SL500 Kits

Shop Strutmasters SL500 Kits

At Strutmasters, our range of suspension conversion kits is designed for easy and ergonomic installation on various car models. What's more, you don't need any modifications to install your new Strutmasters conversion kit, which features American-made SL500 coil springs that offer superior reliability to your OEM suspension system. Additionally, our Strutmasters branded products are covered by our warranty when purchased from an authorized dealer and are far more economically viable. 

As an industry leader with over two decades of experience in suspension manufacturing, we understand the importance of customer service and satisfaction. That is why we have ASE-certified technical support ready to assist you with your Mercedes SL500 conversion kit — contact Strutmasters today via form or email. Alternatively, call us at 866-597-2397 for immediate professional assistance!

Recommended Solutions

Order Your SL500 Conversion Kit Now and Save

If you've decided you've had enough and it's time to switch to one of our conversion kits, we're here to help. Just call 866-984-1443 to talk to one of our Suspension Experts.

« Back to Blog

Have a Question? Call (866) 597-2397 to Speak to a Suspension Expert