Hi all,

The idler pulley on my 07 CLS550 is driving me nuts, so I am thinking of replacing it myself. Does anyone know the procedure for releasing the drive tensioner pulley? Is there a good source for a shop manual available on line?

Thx

 

Can you take a picture of the pulley and/or video of the sound?? I think I have the same problem and would like to compare. Thanks.

 

I recently sprayed the pulleys, and they are OK for now. As soon as the noise returns, I will try to record it for you. Meanwhile, this is the pulley that I am replacing because this is where I believe that the noise is coming from. It could be the tensioner pulley, but this one only cost me $30. If I need to replace another one, I will, but I am starting here.

Sad thing is, for what these cars cost (07 CLS550 with less than 50,000 miles), I must say that I am disappointed, to say the least, that this part fails far to often on these cars.

There should have been a recall.

 

Thanks a lot. That's the exact same part that I think is going on mine. Is your car louder at idle??

 

OK, got the idler pulley done, and while it needed to be replaced, along with the belt, it did not fix the noise. Turns out that the tensioner pulley needs replacing also. Does anyone know where I might find just the pulley? I really don't think that the entire assembly needs to be replaced, but most parts suppliers are selling it as one part.

 

Well that's good to know. Might get a quote on them replacing both at the same time to make sure it's fixed and I won't have to mess with it anymore. Is really pissing me off. Makes me think I've got some raggedy *** car.

 

Idler pulley: $40, Belt Tensioner assembly: $70, and 30 minutes, maybe less if you're handy with a wrench.

 

What kind of milage does the car have? At 62k I had to replace the pulleys and two tensioners. Cost 1100.00 with discount. The double pulley was 450.00 alone. I changed them and it quieted down. That and both belts.

 

Forgot to mention that I used spray to "quiet the pulley" on my W140 1994 S class. Oh it was quiet right up until it let go on the Atlantic City expressway with my wife and son inside. Fortunately my gear head son pulled right off the road. No damage to the head but it cost me 687.00 for the pulley and the belt. Moral: if it squeaks replace it because if not it could be very expensive.

 

My pulley was also changed but under warrantee @39,000 miles. I agree this is very soon for a pulley to start making noise.
Extended warrantee to the rescue, again... Worth it's cost 100x.

 

My 07 cls550 is being shipped but I have the service records and the pulley was replaced at 10k miles.

Geez, it failed at 10k miles?