As you described in your original question, you intended to use the vehicle to commute from home to work. That does not qualify as a business expense, thus making the vehicle ineligible for the 179 deduction.
If the vehicle primarily for business purposes, you may opt for the 179 deduction, but it would be limited to a maximum of $25,000. A 2004 change created this limit unless the GVW is over 14,000 pounds, or one of the following applies:
-- Designed to seat more than nine passengers behind the driver's seat,
-- Equipped with a cargo area (either open or enclosed by a cap) of at least six feet in interior length that is not readily accessible from the passenger compartment, or
-- That has an integral enclosure fully enclosing the driver compartment and load carrying device, does not have seating rearward of the driver's seat, and has no body section protruding more than 30 inches ahead of the leading edge of the windshield.
The remainder of the cost would have to be depreciated over five years. So by opting for this, you may be able to deduct a substantial portion of the cost in the first year, but not all of it.
However, this comes with some very important caveats.
First, Congress is considering reducing or eliminating the 179 deduction for SUV's. They could do this for the 2008 tax year, meaning after you buy the car, that deduction you counted on has disappeared.
Second, even under current law
, if you end up using the vehicle in later years for less than 50% business use or if you sell the car before the end of the five year depreciation period, you may find yourself having to recapture the write off in that year, meaning if business goes bad, you are making less money and working less, you will find yourself also tied to a hefty tax bill to repay part of that initial write off.
But with these caveats, the 179 deduction might work for your situation if you are not primarily using it for commuting. I don't want to breeze over the main point of my initial answer. Commuting costs are not a business expense and a car or truck used exclusively for commuting is not eligible for a business expense of any sort.