well technically speaking you are at fault for hitting vehicle A. Some states might say you were following to closely and did not leave enough room between you and vehicle A. Most places will generally accept that getting hit from behind really trumps this since you could have been stoped and simply let of the brake or some other senario causing you to hit the car in front...because you were startled by car C. What does the police report say....if it states that car c hit a non-moving vehicle B(You) that then hit another non-moving vehicle A.....go get your rental because there ain't a damn thing they can do....You're also entitled to a loss of use claim for x/day times the number of days you're without the car........i'm suprised your tranny got messed up in this....but oh well thats life....if your car is a volvo 240 wagon they'll probalby be totalling your car now if its from the 80's because the repair will be quite high