In late 1999 for the 2000 model year, the CLK range underwent a facelift which incorporated, among other changes, a revised instrument cluster with a bigger multifunction display, steering wheel with controls for the multifunction display and radio, a Tiptronic automatic gearbox, revised bumpers, new side skirts and wing mirror-mounted turn signal repeaters.

The high-performance CLK 55 AMG, which was introduced first in Europe in 2000, is powered by the 5.4 L variant of the M113 V8 engine rated at 347 PS (255 kW; 342 hp); the model was manufactured from 1999, in both the coupé and cabriolet body styles.

Some of the improvements included a reinforced cylinder block, a new cylinder head, individual coil-on-plug ignition with new iridium-tipped spark plugs for longer replacement intervals, connecting rods and pistons capable of a higher compression ratio, dual oxygen sensors and replacement of the Eaton M62 supercharger with the Eaton M45 unit.

The 'dual-resonance' intake manifold with tuned runners helps optimize torque and power output by taking advantage of what Mercedes calls 'resonant frequencies'.

The five-speed automatic transmission (722.6) is fully adaptive and electronically controlled and is a stronger unit than that of the contemporary CLK 430.

Also, a larger four-bolt driveshaft, measuring four inches in diameter, connects to a reinforced rear differential to keep all the extra power under control.

The resulting firmer, more controlled ride is made even tighter by its high-performance ZR-rated low-profile Michelin Pilot Sport tyres.

It was inspired by the AMG-prepared race car that participated in the Deutsche Tourenwagen Masters championship under the factory D2 AMG-Mercedes team.

[14] The model was based on the "Avantgarde" trim with AMG-specific upgrades, including leather sports steering wheel, AMG-badged door sills, gearshift lever and floor mats with the inscription of the edition.

Exterior features included optional Cubanite silver gray metallic paint, 17-inch five-spoke light-alloy wheels, chrome trim and "Final Edition" script on the front fenders.

The interior was finished with Gray Nappa/Alcantara upholstery, wood and leather steering wheel, decorative elements in burr walnut, chrome details and floor mats with "Final Edition" script.

[19] Mercedes used the instrumentation, front grille and the four headlamps for its purpose-built V12 powered mid-engine race car called the Mercedes-Benz CLK-GTR developed for the 1997 FIA GT Championship.