Waiting, with no feedback.

I bought a Mahindra XUV300 from their branch in Polokwane and after a while (maybe a week) I realized that the gears aren't feeling ok, specially the 2nd gear. I took the vehicle back to Mahindra and they said everything is fine and that "some" cars drive like that. Ok, I accepted it, I mean, they are the mechanics, right?? But, after a while, I heard a noise when I started driving and it became louder and louder. So I took it back to the dealership. They inspected the vehicle and told me that they had to send the videos of the sound that the gearbox was making to Mahindra SA and since then it has been a waiting game... If I phone the dealership, they tell me they are waiting for Mahindra SA to know if they give approval for a new gearbox - that has been more than 2 weeks ago. The dealership doesn't keep to their promises, which was to phone me back and give me feedback. If I don't phone them... I don't hear anything. Mahindra SA doesn't respond to them by giving the approval.. The car has just over 16000kms and it already needs a new gearbox?? (I bought the car as a demo with just under 10000kms) With aftersales like this... and all the trouble.. How can I trust to buy another Mahindra? Or support the dealership again? So I have contacted Mahindra SA directly this morning and they said they will follow up if anything was claimed... So let's see how long this will take for feedback..