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2006-2008 Mercedes-Benz CLK-Class

2006
The CLK received a facelift that included a new grill and redesigned tailights. All models received active front head restraints as standard equipment. The CLK320 was replaced with the CLK350. The new engine was a 3.5 liter vee-six with dual overhead cams, variable valve timing, and four-valves per cylinder. This new V6 produced 268 horsepower and was mated to the seven-speed automatic transmission. The CLK350 got new wheels and a new lower front valance. The CLK500 received yet another interior upgrade and an AMG style exhaust tip. The CLK55 coupe was discontuned in the U.S.

The CLK350 coupe had a list price of $46,525, the CLK350 Cabriolet had a list price of $54,475, the CLK500 coupe listed for $55,125, the CLK500 Cabriolet listed for $63,075 and the CLK55 Cabriolet listed for $83,275.

2007
This was the year of the big increase in power. The CLK550 replaced the CLK500. The new engine was a 5.5 liter vee-eight with dual overhead cams, variable valve timing and four-valves per cylinder. The new V8 produced 382 horsepower and 391 pound feet of torque, making it more powerful than the CLK55 AMG. That would be the "old" CLK55 because the new CLK63 replaced it. The new CLK63 produced 475 horsepower, 465 pound feet of torque and a fantastic exhaust note. The only down side was, it wasn't available as a coupe in the U.S. Those who required a CLK63 with a metal roof could order the 506 horsepower CLK63 Black Series.* Since the other models received huge power increases, a new sports appearance package was available for the CLK350.

The CLK350 coupe had a list price of $47,025, the CLK350 Cabriolet had a list price of $55,025, the CLK550 coupe listed for $55,725, the CLK550 Cabriolet listed for $63,725 and the CLK63 Cabriolet listed for $90,025 and the CLK63 Black Series listed for $135,825.

Note: Being a completely different car, the Black Series has it's own web page.

2008
After the previous year, what could Mercedes-Benz possibly change? The CLK350's standard suspension was upgraded to the sports suspension with 18-inch wheels and prices were cut across the board. Not by much, but hey, a discount is a discount.

The CLK350 coupe had a list price of $46,975, the CLK350 Cabriolet had a list price of $54,975, the CLK550 coupe listed for $55,675, the CLK550 Cabriolet listed for $63,675 and the CLK63 Cabriolet listed for $89,975 and the CLK63 Black Series listed for $135,755.

350 / 550 / 63 Caveats

The 3.5 liter vee-sixes have 90 degree blocks. 90 degree vee-sixes are inherently imbalanced. To compensate for this, they have a balance shaft that spins in the opposite direction of the crankshaft. That makes the engine run very smooth. The balance shaft has a gear on the end and it is driven by the timing chain. Unfortunately, the gear on the balance shaft is sintered steel and it wears quickly. With a worn gear, the cam timing is thrown off. Accurate cam positioning is critical on an engine with variable valve timing. When the positioning is determined to be off, the check engine light illuminates. This is not something that can be ignored. If the gear is worn it must be replaced, or things can get very expensive. Not that replacing the balance shaft gear is inexpensive. This is one of the few repairs that require the engine be removed from the car. The M112 based 3.2 liter vee-six didn't have this issue. This only engines effected are 3.5 liter type M272s up to engine serial number 468993.

Unfortunately, the early M273s had a similar issue to those of the M272. The M273 doesn't use a balance shaft because a 90-degree cylinder angle is ideal for vee-eights. Unfortunately, it has an idle gear where the balance shaft would be and that gear has the same inferior metallurgy as the one in the vee-six. After Mercedes-Benz identified this as a problem, the sintered steel gear was replaced with one using conventional steel. M273 engines up to serial number 088611 have the bad idle gear.

The CLK63 engine has some serious top end issues. Those can be seen at the bottom of this page.

The upside to all these issues is many dealers are making repairs under warrantee .

Technical Data (2007)

© 2008 Marcus Blair Fitzhugh

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