I've towed horse trailers with my 31 ft MH.
That said the MOST important thing is the hitch. I spent well over $1,000 to have the 'correct' hitch put on my MH for hauling my 2 and 4 place trailers. Take your MH to a horse trailer dealership and get the lowdown on what we do to our MH's to make them horse worthy. The hitch the MH came with is most likely not going to hack it.
You will struggle with pulling with an 8 cyl and be at or over your towing capacity when loaded up. Probably not what you wanted to hear but better now than later on down the road.
