Stiggs

This moring was very cold. Maybe 20 degrees F.
I started my ML430 up early and heard a strange noise. Sounded like metal or plastic rattling around. Almost as if something was loose. I opened up the hood and the noise was not in the engine. It was coming from under the truck. Almost as if a squirrel was under there running around. I couldn't pinpoint where exactly the noise was coming from....almost towards the back of the truck. Definitely not the engine. This was happening when the truck was idle in park. The truck drove well....no problems on the road. When I got to work I kept the truck running in park and went outside to see if the noise was still there. Fortunately the niose was gone.
was this a cold weather problem?

Again almost sounded as if something was loose and rattling around or against something.

Not much to work with here...sorry. I will see if it happens again tomorrow morning since it will be cold and snowing here!
Thanks for the opinions on this.
Stiggs

Stiggs

OK....I did a search here and found that most people that have this rattle said it was the cats. Is it true these are covered for free until 88K miles?

I guess I should have done the search first huh?