Regarding if MB will give you a balancer at no charge depends how old your vehicle is; if you are the original owner;and how often you come in to the dealer for work. The part isn't very expensive at the dealer, but i am unsure what they go for in the after market world. The hardest part of the job is removing/ installing the balancer bolt. There is a special tool used that fits in the balancer to hold it. I usually replace the front crank shaft seal (there is also a special tool to install seal),balancer, and bolt (being a stretch bolt). The torque spec is 150 ft-lbs and then 90 degrees when installing.If you decide to do this job, i can supply you with more info, but he dealer only charges about an hour(or call an independent shop), so it might not be worth the headache.Good luck.