Transmission Squeak

Transmission problem
2003 Range Rover V8 Automatic 64,000 miles

Hi.I have a 2003 Range Rover with 64,000.I bought it used and have had it for 3 months now.I've had a few problems with the radio playing when it feels like it. But recently I heard a squeak and felt some slipping. Took it to the dealer and after a inspection from "The Inspector" I was told the transmission is bad and it's not covered by the warranty because the cause of the problem was found to have started with the radiator(which is not covered by warranty). Repairs will cost $6000. My question is how does the radiator have anything to do with the transmission and is there anything I can do to get around this issue without dishing out so much money? I can't believe that a truck with such low miles would have a major issue like this or that I should have to pay for a faulty radiator that caused my transmission to go.