Lemon Law: Help

My question involves a consumer law issue in the State of Texas: Around November 20th 2014 I purchased a 2005 used ford explorer. During the test drive I noticed a whistling noise coming from the rear of the vehicle. They told me they would fix it BBefore I purchased it. Two days later they called and said the problem was in the rear end of the vehicle and that it had been fixed. They put that i had a 1 year warrenty on this part.So I proceeded to buy the vehicle since every thing seemed okay. Two months later on January of 15th of 2015 my wife is driving down the road and hears a grinding noise coming from the rear of the vehicle again. I dropped the vehicle off that day to have them look at it. It has now been over a month since I have seen the vehicle. When I call they say that it is the transmission and they are trying to get parts or trying to get someone to fix it and they are saying that the transmission is not covered under the warranty but they're going to make it right.well I called today they ignored my first two calls but on the third she finally answered and said my vehicle was at the transmission shop being looked at. Well I drove to the transmission shop too see if it was there, and it was nowhere to be seen. I really just want my money back at this point. What can I do?



Just for the record I am still paying for the vehicle and I haven't seen it in over a month.

Lemon Law: Help