Mercedes-Benz V12-engined technological tour-de-force is also one of the most opulent rides on the street, making the W220 S600 S-class a seriously desirable, if potentially wallet-crippling, used car buy.

Originally dubbed Sonderklasse, which translates from its native German to ‘special class’ in English – and later abbreviated to simply S-Class – the Mercedes-Benz S-Class is the Bavarian motor manufacturer’s top-of-the-range series of luxury saloons and limousines. Introduced in 1972 with the W116 – the first production car to get ABS – the moniker has remained in use ever since to denote the brand’s flagship vehicles.

Mercedes-Benz S-Class history

Renowned for debuting the firm’s latest innovations including drivetrain technology, interior features and safety and driver assistance systems, the S-Class is a model that has always been at the bleeding edge of automotive technology, packed into a sublime-riding saloon body with creamy powerplants and opulent interiors.

The W220 generation launched in July 1998 featuring smaller overall exterior dimensions, improved aerodynamics and a lighter weight than its W140 predecessor, yet offering even greater interior space.

The model was the first to introduce the brand’s new Airmatic air suspension system, as well as an advanced electronic driver control system marketed as COMAND. Other top tech included keyless entry and ignition, Distronic radar-controlled cruise control and Active Cylinder control, which would shut-down a bank of cylinders to improve fuel economy. North American owners could also benefit from a new all-wheel drive system known as 4MATIC, while in 2002, along with an exterior face-lift, Mercedes-Benz introduced the world’s first pre-emptive safety system on the W220, called Pre-Safe.

Although a host of powerplant options were available, starting with 2.8-litre V6 petrol and 3.2-liter inline-six diesel engines, we’re focusing this guide on the brutish S600 model, equipped with either a 5.8-liter naturally aspirated or 5.5-liter twin turbocharged V12 engines; unleashed on the world in 2001. We love this car so much, we placed it in our list of the best used sedans you can buy.

static shot of mercedes-benz s600

Mercedes-Benz S600 W220 most common problems

  • Rust – A raft of cost-cutting measures in Mercedes-Benz production around this time, including the use of poorer-quality steel and a switch to non-solvent water-based paint, means the W220-generation S600s do suffer from corrosion. Found often around the arches, bootlid and suspension turrets. Facelift versions are often less affected, but are still susceptible.
  • Airmatic suspension – While the Airmatic suspension system is the reason for the S600’s silky smooth ride, air leaks from the system are common and usually occur at the strut tops and from the pump pipework. Pumps can also fail and will need replacing and recalibrating with a star machine when installed.
  • Battery drains – The S600 is absolutely brimming with tech, but this takes a heavy toll on the car’s battery, leaving it without sufficient cranking amps to start the car. Sometimes down to an electrical fault, which can be a minefield to diagnose, or just the age of the electronics. The best bet is to keep the battery topped up with a trickle charger if not used for even short spells.
  • ABC pump – Whereas some models use the Airmatic system, later cars and some early cars that specified it as an optional upgrade, run a hydropneumatic system called Active Body Control, which uses hydraulic fluid to actively change the pressure of the springs inside the damper assemblies, changing vehicle dynamics and ride height. The pump for this system is incorporated into the power steering pump, and can often lose its ability to deliver adequate pressure over time or can fail completely, leading to a low or uneven ride height and a warning message on the dash.

Mercedes S600 Pros

  • Both 5.8-litre naturally aspirated and 5.5-liter twin turbocharged V12 engines give prodigious shove, equipping the S600 with effortless supercar rivalling pace that sounds the part too
  • Sublime ride quality that will allow you to cross continents in comfort and style, cosseted in sumptuous climate-controlled leather massage seats
  • If you are a gadget fan, the S600 has enough top tech to keep you entertained for a lifetime!

Mercedes S600 Cons

  • Naturally aspirated M137 V12 is noted as being one of Mercedes-Benz most unreliable engines, with big bills from a plethora of pricey failings very likely looming on the horizon
  • This might sound obvious to some, but the running costs of these luxury laden barges is astronomical, and let’s not even mention the fuel economy!
  • Early, pre-facelift cars are prone to corrosion problems so check for signs of body repairs, welding and overspray, or bubbling paintwork around arches, boot suspension turrets

rear shot of Merc W220

Mercedes-Benz S-Class Model timeline

  • 1972 – First generation of Mercedes-Benz’ luxury saloon range to be coined S-Class with the W116 model, the first car to come with anti-lock brakes.
  • 1979 – Second generation S-Class introduced. The W126 featuring ground-breaking safety features such as seatbelt pretensioners and driver airbag.
  • 1991 – Third generation S-Class W140 launched with ESP and side airbag safety features and voice activated phone operation.
  • 1998 – Fourth generation S-Class W220 introduced at the Paris Motor Show in September with adaptive cruise control and air suspension.
  • 2001 – S600 model launched with 5.8-liter 36v M137 V12 engine.
  • 2002 – Facelift S600 launched with 5.5-liter 36v twin turbo M275 engine.
  • 2005 – Fifth generation S-Class W221 introduced with even more tech and a the option of a hybrid powerplant.
  • 2013 – Sixth generation S-Class W222 launched with a 50% aluminum shell and road-scanning Magic Body Control suspension.
  • 2020 – Seventh generation S-Class debuted featuring a nine-speed transmission, augmented head-up display and rear seat ambient-fill airbags.
v12 engine in mercedes W220

Mercedes-Benz S600 V12 Engine

Early S600 models came with the naturally aspirated 5.8-liter M137 V12 engine. While undoubtedly a potent lump, it has gone on to be regarded as Mercedes-Benz least reliable engine ever made. Along with a host of other issues, one of the main concerns in cylinder wall deformation. This causes the cylinder walls to become out-of-round allowing oil to pass into the combustion chamber. Once this happens, there’s no saving it and a replacement engine is the only option, which is not cheap at around $34,000 or £26,000. Oil fouling is also a concern, which can lead to a list of expensive failures including the catalytic converters.

The face-lifted models from 2003 onwards used the twin turbocharged 5.5-litre M275 V12, which is a much more robust unit that is regarded as one of the best Mercedes-Benz engines of all time – how’s that for a turnaround?! The blown unit produces 493bhp and 590 lb ft of torque at just 1800rpm, allowing it to complete the 0-60mph sprint in just 4.3 seconds, all while remaining largely trouble-free. The only thing recommended on top of regular maintenance is to replace the coilpacks every 60k miles at a cost of around $1000 / £780 per cylinder bank. The only other downside is fuel economy, which will run in the low to mid-teens if you’re careful, but let that V12 sing and you’ll likely drop into single digits!

Transmission

All models of the W220 S600 come with five-speed automatic gearboxes, as the seven-speed 7G-tronic boxes that are optional in early cars and standard equipment from 2006 onwards on the lesser-powered models, are simply not strong enough to contend with the V12’s torque in the S600. Both gearboxes have self-adjusting mechanisms that are supposed to make shifts soft even when the gearbox is cold, so make sure to test drive the car when cold to ensure these contraptions work as they are supposed to and the shifts remain silky smooth. Any hesitation of jerky shifts could indicate expensive problems that can be tricky to diagnose.

side profile shot of mercedes-benz s600

Mercedes-Benz S600 Suspension

As we explained earlier, S600s come with either Airmatic or Active Body Control suspension systems, both of which when working correctly, will provide the big Merc with peerless ride quality and the kind of handling dynamics that defy physics for such a weighty car. However, with this complexity comes a greater chance for problems and any leaks in the air system or issues with the ABC pump or its plethora of related components can cause the ride height to sag either at one corner, or any combination of all four corners. This obviously impedes their functionality and will require fixing, which could be as simple as a leaking air-line, or a complete replacement pump, which while not super expensive as a part, does require a fair amount of labor to fit.

When viewing check ride height raises to the proper level and all corners are the same height, also listen out for any creaks or squeaks on the test drive, as this could indicate worn lower control arm bushings.

Brakes

As an extremely powerful and heavy car, the Mercedes-Benz S600 has an equally meaty braking system, able to haul the luxo-barge up from three-figure speeds with ease. However, repeated hard braking will wear the rotors and pads much faster and potentially induce warping of the discs. On the test drive check for any pulling or vibrations under hard braking. Also, the S600 is fitted with a Sensotronic Brake Control (SBC) pump, which is part of the brake-by-wire system.

This pump has a life expectancy that works off the number of brake actuations, which once past this pre-set figure, will illuminate a warning light on the dash and reduce pressure to the braking system. A replacement pump can cost in the region of $4000 / £3000 once fitting and calibration has been carried out, although remanufacturing of the pump is also possible to rectify the issue at a lower cost.

interior shot of mercedes-benz s600

Wheels & Tires 

The Mercedes-Benz S600 W220 comes with 8 or 8.5x18in wheels as standard with a 5×112 PCD and an offset of ET44, but the car’s huge arches will easily swallow 19s or even 20s if you fancy an upgrade to some more stand-out rolling stock. Whatever wheels your prospective purchase is wearing however, it’s worth checking the condition of the wheels for any signs of curbing or corrosion, or any cracks that would need immediate repair. While your down there, have a look at the tires. Do they have plenty of tread across the entire width of the tire and are they all the same good quality brand? Someone who owns a luxury car like this needs to pay attention to the details and not skimp when it comes to maintenance, so poor quality mismatched tires is a definite red flag that could prove costly if ignored.

Mercedes-Benz S600 W220 Prices

In the US, early 2001 non twin-turbo cars with high mileage start from around $13,000. Naturally, this price climbs as the condition of the car improves. For a twin-turbo car, expect to pay upwards of $25,000. In the UK, that figure is drastically lower, in fact, you can pick up twin-turbo S600 cars from as little as £7,000. Although remember, the mechanicals on this car can become costly when faulty, so while the car may be under £10,000, expect costly repairs sooner rather than later.

Words: Dan Sherwood.