I have a 2008 300C.Louud suspension noise on left turn and sometimes straigh. Sould like rattle and ...

Sounds like a ball joint or tie-rod - if it is a new car you should take it to the dealership immediately aand have it looked at - anything like that would be warranty

Right, this is warranty issue.  Could also be a strut problem.

Did you go with 20s or 22s !?....If you didnt have them set up with lifters or spacers it might be rubbing. Tie rods might be another issue as well as rocker arms.... The car was not intended to roll with oversize wheels...although it may look nice...It may also void the factory warranty and your going to spending alot of loot down the line !!

i have found the outer tie rods to get loose, this usually occurs after 13k, also the link between the stg knuckle and the engine cradle, and a few lower ball joints. gt it to the dealer for warrnty