All the Manual says is 1000miles before towing and no dead start full throttle starts for first 500 miles of towing. I myself will be pushing the 1000 mile mark before I tow. If I can get 800+ and be real easy towing. When I got new gears in my old pickup they recommended 500 miles before towing. But it's your truck. Iv known some people to tow heavy from the start, they think it's the best way to break it in. But IMO i think it's best to get at least 500-1,000 miles.