You mean work without any modifications and as straight bolt on?
if it works then most likely it would mean that you can put CLK430 brake kits onto an ML55 if they were interexchangeable. I know the rears might not work because the ML rear disc has the parking brake shoes inside.
Also, why would you like to do this since it's not even a good brake kit. I'm trying to get rid of mines.
don't have the ML anymore, but just sharing what i know.
the ML has completely different hat/rotor than the CLK. The caliper would most likely need to be machined at the mounting bracket or extra mounting braket has to be machined. the rotors will not work at all.
W208 can use the front brakes from W202 and W210 as far as i know. It'll be easier for you to get the W203 bbk i.e. the C32/55 or the 05+ sport brakes from the C230/350 sports. you'll still need to modify the bracket tho.
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2002 M112K with lots of mods
2008 M272 with some mods