I think there have been valid points on either side of the "for or against" argument....heres my .02....

1) At the end of the day its only a vehicle....sure, the trip may depreciate its value, but I'd think the memories of such an excursion would farrrr out weigh that---you can always buy another X5.
2) Do it in a vehicle you actually want to be in for that amount of time. Last thing you want is to be stuck driving that distance in a vehicle you don't enjoy. I'm sorry, but the idea of being stuck in a pickup for that length of time is complete rubbish. They ride and handle like crap; the last place Id want to be is traveling the twisted mountain roads in one of those crude things. If its a leisure trip, it has to be a vehicle you enjoy driving.
3) Preparation, Preparation, Preparation....Spare parts, tools, survival gear, maps; But most of all, don't be cheap...get yourself a satellite phone. If you happen to actually need help somewhere out of range of normal cell towers, last thing you want is to have to wait for someone to come along to flag.
4) Give your truck an excruciating check up. Up, under, over and through....then again! Compare known problem areas to past maintenance to see If anything may be a problem down the road.

Granted, there's always the possibility of the unforeseen....BUT, with proper planning should have no troubles minimizing it. Take the time and spend the dough to plan it correctly and go for it!!

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