2008 Mercedes-Benz SLK (R171)

General information & model overview

Body & dimensions

Engine specifications (facelift focus)

Drivetrain & transmission

Chassis, equipment & facelift changes

Performance (approximate)

Image source: Wikimedia Commons

What the 2008 SLK facelift is

The 2008 Mercedes-Benz SLK is the mid-cycle refresh of the second-generation R171 roadster. It is not a new chassis code. It is the same two-seat hardtop roadster architecture introduced in 2004, with stronger four- and six-cylinder outputs, revised exterior aero styling, updated electronics, and refined steering options. Production continued until the R172 arrived in 2011.

For the original R171 launch specification and early SLK 350 / 55 AMG context, see the 2004 R171 entry.

Facelift changes that matter

1. Power increases

The SLK 200 Kompressor rose to about 184 PS. The SLK 350 rose to about 306 PS with higher rev capability. Efficiency and CO2 figures were also reworked on several engines. These changes are the main mechanical reasons to distinguish a post-2008 car from a 2004–2007 example when shopping or cataloguing.

2. Exterior and interior refresh

Arrow-shaped front air dams, a more aggressive rear diffuser graphic, LED mirror indicators, and new wheels update the Formula One–inspired nose language of the early R171. Inside, the instrument and COMAND-era systems move to NTG 2.5 with optional voice control and upgraded audio.

3. Direct steering and AMG

Variable direct-steer assistance became optional on regular cars and standard on the SLK 55 AMG. The AMG V8 retained roughly 360 PS; SPEEDSHIFT calibration on facelift cars shifted slightly faster according to period factory notes.

Image source: Wikimedia Commons

Driving character of the late R171

Late R171 cars remain compact grand-touring roadsters rather than track specials. The 306 PS SLK 350 with manual gearbox was praised in period as one of the more engaging Mercedes convertibles of its time. The 55 AMG delivers V8 sound and straight-line pace with a firmer ride. Airscarf and the solid hardtop keep the car usable in cool weather better than many fabric rivals.

Ownership notes for facelift cars

1. Confirm facelift identity

Use lights, bumpers, mirrors, and engine output codes — not only model year badges — to separate facelift from pre-facelift R171s.

2. Shared R171 systems

Roof mechanisms, Airscarf hardware, balance-shaft and timing themes on M272 V6s, and supercharger maintenance on M271 fours are known specialist topics. The 55 AMG’s large brakes and V8 cooling need correct fluid and pad history.

3. Manual six-cylinder rarity

R171 was the last SLK generation to offer manual gearboxes on V6 models in many markets. Document transmission type carefully; it affects both driving character and collector interest.

Engines in daily use after the 2008 changes

The jump from 163 to 184 PS on the 200 Kompressor and from 272 to 306 PS on the 350 is noticeable in overtaking and on-ramp work. Higher compression and revised intake and valvetrain details also raised the temporary rev ceiling on several engines. Fuel economy marketing improved on paper; real open-roof use still consumes more than brochure combined figures. The 55 AMG remained the outlier for sound and cost of consumables — tyres, brakes, and fuel.

Cabin and electronics of late R171

NTG 2.5 brought the car into the late-2000s Mercedes multimedia generation. Bluetooth, navigation, and audio options are more usable than early COMAND systems but still lag modern phone-centric interfaces. Airscarf, heated seats, and Thermotronic climate control define cold-weather open-top usability. Leather and Designo colours from this era remain popular; check for cracked dash tops and worn seat bolsters on high-sun cars.

Buying a facelift versus waiting for R172

Late R171 cars often cost less than early R172s while offering V6 manuals and a proven roof design. Buyers who want diesel efficiency or Magic Sky Control must move to R172. Buyers who want a supercharged four or a naturally aspirated V6 with a stick can stay in facelift R171 with fewer electronic layers to age.

Legacy

The 2008 facelift is the polished final form of the R171: stronger engines, cleaner electronics, and sharper detailing before the all-new R172. Durable facts: R171 facelift from 2008, Bremen build, Vario roof, Airscarf, 184–360 PS mainstream/AMG range, production into 2011.