impact wrench - electric

Too bad, I've already committed to give my dad's old Snap-on electric impact wrench to my brother-in-law's brother.

If you are going to use it a lot (like every day), get a Snap-On or invest in an air compressor and pneumatic impact wrench.

If you are only going to use it occasionally, like for rotating tires, then almost any brand is probably good enough. I'd look at Milwaukee, Makita, DeWalt, Skill/Bosch, Hitachi, and Craftsman. Places like Home Depot, Sears, and Loews should sell them. Snap-On makes a professional grade one although you have to catch a Snap-On dealer's truck and you'll pay dearly. My opinion of Craftsman power tools is that although they cost less than much of the competition, they tend to be bigger and bulkier than one with comparable features from most of the other tool makers but are fine for occasional use.

I have never used a 12 volt impact wrench so I do not know how well it works. If I were shopping for a non-pneumatic impact for use in a garage, I'd stick to 120 volt ones. I would not get a cordless one unless you are looking for portability.

Newark has a Harbor Freight and they sell an inexpensive Chicago Electric impact wrench that might work for your needs. Be sure to get the extended warranty.

However, if you plan to work on your car quite a bit, consider investing in an air compressor and air tools. Best investment I have made in a long time and good air tools are inexpensive. A decent air impact wrench (over 250 ft/lbs torque) would run under $30.