Rudeney

Well, about a week after having the conductor plate int he CLK550's 722.9 replaced, I have an update. The conductor plate seems fine. It shifts well and seems more responsive to throttle input. However, the "click-click" noises are still there. I hear them when shifting into D or R and when changing gears at low speed (the only time I can hear it over road noise). It sounds like two pool ***** clicking together.

Also, just before the conductor plate died, I was hearing this odd "ticking" noise at idle, and it's still there. this sounds like a bad valve tap. It doesn't make noise on a cold engine, but a few minutes after running I can hear it and it seems louder after reaching full operating temp. It's loud enough that if you were stopped in traffic next to me, you'd hear it. It goes away (or is drowned out with other engine noise) around 1,500 RPM. It's really hard to pinpoint the source, but if I had to guess, it's in the transmission. I've tried a stethoscope and still can't pinpoint it, though it was really hot in the garage and I only spent a few minutes poking around.

I was hoping both of those issues were part of the conductor plate failure, but apparently not. I'm suspecting it's in the torque converter, but not sure. I know the main fluid pumps in the early 722.9's were prone to failure.

Amir_AMG

sounds like a very tricky problem..very nice of you to post your findings and updates so that members in the future can look this problem up if having the same issue

DanielFD

The tick tick sounds when changing gears sounds most likely to be a small bushing under the gear selector that goes bad, I've heard its pretty simply to test and fix; but honestly i know nothing about it.

Rudeney

The clicking sounds when changing gears are definitely not the shifter bushings. I have that sound on the C240 and know what it is. Like I said, this sounds like two pool ***** clicking together, and it does it after shifting into gear, right as the car start to move. Sometimes when coming to a stop as it downshifts I also hear it, and I can hear it when it shifts from 1-2 and maybe 2-3 if I listen carefully, but it does not always make the noise.

The ticking noise is faster than engine RM. When I first hear it, I thought alternator or AC compressor, but it's definitely not coming from there. Maybe if I have a chance this weekend, I'll lift it and remove the underbody panels and listen more carefully. Or, maybe I'll just do yard work, float in the pool, and when I drive, turn the radio louder.

gaazmon

Do you get this "clicking" noise when going uphill in reverse? I get clicking noises also sometimes if I put it in D or R and take off too quickly before letting it settle in gear and it goes "click "click "click" as I takeoff. Also, sometimes when it downshifts to abruptly from 2nd to 1st.

DanielFD

@gaazmon sounds you like have worn control bushings. or if its more then one click and towards the rear its most probably your rear hubs (forgot what they are called, the part of rear axle that connects the wheel to the rear axle bar) need some lubrication or they are worn.

mrbobby

The early 7 speeds were such a pain in the butt because, if you were a boater, you would say "it's just a hole in the water that you throw money at". I suspect the noise it just the sound of money slowly emptying from your piggy bank. Take it to the dealer. They can empty the piggy bank much faster.

Spoken by an ex 722.9 owner ('05 CLK 500) who finally gave up and went back to the S class. Even in '08 the 722.9 isn't as good as the old 5 speed. Please forgive me, we all know this, I'm just re-chewing old garbage.

Rudeney

Hmm, I don't often go uphill in reverse, so I can't say much about that, but the click-click happens most (but not all) of the time when I shift into gear from park and when I start off from a stop. For example, I get in the car in the morning in the garage, start the engine, put in in R and just before I give it some gas to back out, I hear the click-click. Then once I back into the driveway and alley and put it in drive to go forward, I hear click-click. I stop at an intersection, and give it gas to go and hear the click-click right as it starts off. But as I said, not always.

as for the ticking sound, I was in a fast food drive through on he way home today (kid was craving some junk food) and heard it. But when I got home and pulled in the garage, it was silent. I have noticed that the "beat" of this noise is much faster than the engine RPM. It does not seem to affect anything. I once had an odd noise on the C240 like this and it turned out to be a piece of sound deadening insulation contacting the drive shaft. I am hoping this is something equally as benign.

kiroCLK

Hi, Rodney I know it's a very old thread, but I'm having the same noise as you describe. Were you able to find what was the cause?