A new base engine highlights 2006 for these 4-passenger coupes and convertibles. CLK coupes have hardtop styling with no middle roof posts. Convertibles have a power fabric top, heated glass rear window, and roll bars in the rear headrests designed to pop up in an impending rollover. Three model levels are offered. Replacing the CLK320 and its 215-hp 3.2-liter V6 for 2006 is the CLK350 with a 268-hp 3.5-liter V6. Returning is the CLK500 with its 302-hp V8. CLK350 and CLK500 are offered in both body styles. Available for 2006 as a convertible only is the high-performance CLK55 with a 362-hp V8 developed by Mercedes' AMG performance arm. All CLKs have an automatic transmission, a 5-speed in CLK55s, a 7-speed in the others. All have a manual shift gate, with V8 models also getting manual-shift steering-wheel buttons. All CLKs come with ABS and traction/antiskid control. Front side airbags are standard; the convertibles' cover head and torso. Coupes have curtain side airbags. Rear side airbags are standard on CLK55s, optional on the others. CLK55s also include a sport suspension and 18-inch wheels vs. the others' 17s. All models get a revised grille and taillamps for '06. They come with Mercedes' TeleAid assistance. Mercedes' COMAND video-screen control for audio and available navigation and phone systems, is optional. So is Mercedes' Keyless Go, which uses a pocket transmitter for ignition and door-lock operation.
 

Fuel and ignition system ME 2.8 engine management. Integrated sequential multipoint fuel injection and phased twin-spark ignition includes individual cylinder control of fuel spray, spark timing and phase, and antiknock. Electronic throttle. Two high-energy ignition coils and two spark plugs per cylinder, with 100,000-mile spark plug intervals.

Intake system Helical high-pressure supercharger with liquid-to-air intercooler and electromagnetic clutch. 11.6 psi maximum boost.

Transfer Case 2-speed, electronically controlled via console switch. Display in instrument cluster indicates selected transfer-case range.

Transmission Driver-adaptive electronic 5-speed automatic. Touch Shift allows driver to manually downshift and allow upshifts by nudging the shift lever left or right from the Drive position. Shift into Optimum Gear programming allows one-touch selection of the best gear for maximum acceleration or engine braking by holding the shift lever to the left of Drive for one second. Display in instrument cluster indicates selected gear range.

Drive System Permanent full-time 4-wheel drive, with 50/50 front/rear torque split and electromechanically locking center, rear and front differentials, sequentially activated by driver.^{1 2 3}

Transfer case ratio 0.87:1 normal range/2.16:1 low range.

Front and rear axle ratio 4.38:1