My Xbox360 is making a funny sound, it goes 'brick brick brick brick'

No, really, I got the feared 3-bar red ring of death No good reason, it just went kaput.

What I have heard is that Microsoft extened their warranty for this specific problem (3 bar RROD, not 4 bar, not 2 bar) for 3 years because they were having something like a 33% failure rate.

Well I got mine used from a videogame store, do you know if this warranty will still apply since its a defective product?