Sorry to hear about your misfortune. Make sure that you are treated fair by the insurance company. I am not saying that you would but don't gouge them just like you don't want to be gouged. Unless the truck driver dropped the drive shaft on purpose so you WOULD hit it then it is still an accident.

Be prepared for the adjuster to more than likely "low-ball" the damage estimate. Have all your "ducks in a row" and push the adjuster to treat you right. If MB repair shops normally do your repairs then let them give you the estimates for repair. If Billy Bob's Benz Barn normally does your repairs, because he's FAIR, then get BBBB to give you an estimate for repairs. You need to be taken care of in this matter. You never can tell when YOU might have a claim taken against your insurance.

BTW, if the truck driver has State Farm Insurance then please be easy on him. I don't want to have to help him pay for your repairs. :p