I have no idea whether or not the Blazer had a trailering special...but it would make sense. Mine says 9 000 G.C.W, 350ci, 2WD, and trailer towing stuff. I think it may have received the better transmission options...but, like yourself, I don't have much of an idea. You can try and find out on the web, but most places are devoted to 4X4's like coloradok5.com. If you have any info beyond what I told you, you know more than I do. LOL.