Mercedes Benz Mercedez Benz - Defective Parts Montvale, New Jersey

"  Please investigate and hold them accountable. "

I have investigated and I find that you have posted nothing that they should be accountable for.   The warranty covers defects for a given period of time and mileage.   After that, the owner is required to pick up the tab if a part fails.    What is so difficult to understand about that?

All car manufacturers make less than perfect cars with less than perfectly designed parts.   Expecting that you deserve warranty coverage after the warranty period is over is wishful thinking at best.   If Mercedes wanted to provide such coverage, they would have.

What your case really boils down to is that your old car has an expensive problem and (in true American style) you want someone else to be responsible for what is plainly your responsiblility.  Good luck with that.

NHTSA recalls are for safety issues so a balance shaft sprocket would not be recalled.

I don't know how long the Mercedes warranty is but if it's expired they don't have any obligation to fix it.  They could, to generate good will,  but I would not hold my breath.