06 colorado 4x4 transmission compatible with the 07 hummer h3?

 

You will at least need your old pan. There is a cut out on the H3 tranmission pan for the front drive shaft.

Someone else will need to speak to the electrical compatibility.

 

Why do you need a swap? Rebuild the Trans you already have.

An 06 Colly 4L60E will work in an H3 so long as you make sure to use the correct pan. I thought I recall something may be different in the Valve Body as well so check that out.