There I bought a Land Rover Discovery2.

Hi there
I bought a Land Rover Discovery2 V8 automatic in December 2012 and drove about 1500km with it when I got stuck with it. I was going uphill doing 70km/h when it started overrevving and jerking. When I got to the top of the hill I stopped, to check what wrong, I saw that the lights next to the gearlever was flashing. So I got towed home with a rollback.
When I got home the car was cooled off the I started it again to check if its still doing I same. I putting it in drive and could hear it go in gear, but as I left the brake it doesn't move. I had to rev it up to about 4500rpm then it only moves.
The dealership where I bought it sent it to a Land Rover specialist and they said the damages is about R23000.00, but we can buy a second gearbox for R15000.00 with installation and I must pay for this. I consulted and ombudsman and he said they must fix it. I told them about this now they say the clutches in the box needs replacing and it part of "wear and tear".
Is that part of wear and tear? I only had the car for two weeks and did about 1500km.

Please help