Hector, the 1 1/2" socket would be the one you would use. I don't think 1 1/2" is the exact size but it works fine and my SAE sockets don't have anything else that fits. It may be a 38MM since the 1 1/2" is a little large but since I'm cheap I don't plan on buying 1" metric impacts.
As cool as the X-12 is, a 4 ft. piece of 2" pipe will do the job just as well and I'm not so sure that you might not mar up a wheel with the X-12. Like Mike says, break um loose and use a good 1/2" impact to do the work.
If you buy a 1" impact from a Harbor Freight store, you will have to get 1/2" air hose somewhere else. They have 1/2" online but not in their retail stores.
Mike, I got this one on sale for about a hundred bucks. Works fine but the darn thing will work your tush off it's so heavy. Wish I had bought one twenty years ago.
http://www.harborfreight.com/cpi/cta...emnumber=94109