Bought a vehicle that broke 80 km further.

I bought a 2005 BMW 525 I from Auric BMW on the 5th of January 2015. I went down to Cape Town on the 8th of January to collect the vehicle. I made it as far as Worcester where the vehicle broke down. Worcester BMW quoted me R50 000 to repair the gearbox. Auric BMW feels that is not their responsibility and refuses to either cancel or repair the vehicle. I have forwarded legal letters but still with no satisfaction. I am work for a dealership myself but purchased this vehicle for myself. It is dealers like Auric BMW that give the rest of us a bad reputation. It is now already three months and I still don't have a car or my money back...The car is still standing in Worcester..