SilverDameon55

Hey all, I just recently purchased an 09' ML350 for my wife. This was a one owner car with 109K miles on it. I just recently took it to my mechanic who's a certified euro mechanic to have a complete check up and system flush (since I noticed the coolent in the car wasn't blue). Upon inspection he told me that the 2 main pulleys and idler pulley needs to be replaced. I asked why and he stated that at 100K miles they should have been changed but weren't. He told me the main "ribed" pulley must be changed soon as it grinds when he turns it by hand. Is it true they all have to be changed at 100K miles? And if so, is there a place to get them or is it recommended to use OEM? Thanks

Maj. Dundee

What color was the coolant?

What do you mean by the two main pulleys?

SilverDameon55

The coolent was a dirty water color with a hint of green. It appeared that they put 50/50 and water in it. As for the pulleys, he said that a "ribbed" one, a "smooth" one and the ideler pulley should have been changed.

SilverDameon55

Based on that diagram picture, I will assume it's #1,#2 & #3 that he is stating should be replaced.

Maj. Dundee

Green coolant is the wrong type and the entire cooling system must be flushed.

Only gold coolant Zerex G-05 or M/B blue coolant should be used.

So change the pulleys that were indicated by your mechanic.