Towing up and down Grapevine with that little SUV is asking for trouble. Go rent a Suburban or similar with a V8 and enjoy. We farmed in Tulare and Kern Counties for years, driven trucks, pulled all kinds of trailers, and a big Class C over GV many dozens of times and no way would I do what you propose. Grapevine can be tricky, especially when windy (often), panic stops are scary, and the downhill gravity is strong and why GV has runaway exits..God forbid. You get a inexperienced driver who hit the brakes or cuts off drivers and that Kia is not something I would like to be in with a panic stop. Rent or borrow a safe tow vehicle. Ford Expedition will safely to the job.