This has been gone over many times here. You have an 11 and almost 12 year old vehicle. You will be waaaaay ahead to sell it and buy one that is already equiped with the 4 wheel drive you would like.
The down time and effort required to find all the correct parts and install them correctly would probably surpass the value of your present vehicle.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

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