I know this is an old thread, but I use a number of trailering methods which I think work well. First, per DOT regs and common sense, total load ratings of tie-downs should be at least 1.5 times the weight of the equipment (cargo). I use chain since the rebound, and potential acceleration of the cargo in wierd directions, possible with nylon straps makes me nervous when talking about tens of thousands of dollars of equipment and the safety of peoples' lives, including others' lives. An out-of-control load and rig can be lethal to anyone near it particularly at highway speeds. In other words, a 6000 lb tractor (JD 4700 with loader and loaded tires) should have total tie-downs rated at least 9000 lbs. This implies transport-rated (gold colored) chain and not your basic silver colored stuff. I use my heaviest chains on the rear, since sudden braking is the most foreseeable emergency (I'm not likely to accelerate so hard as to challenge the front chain). Similarly, if I have enough, I'll use a safety chain on the rear passed through the drawbar frame, with the first chain fastened to the drawbar with a clevis. The clevis/pin/drawbar combo makes it easy to drop at least that chain while you're at the worksite without pulling everything apart. Get the tractor positioned correctly fore and aft on the trailer for tongue weight, tighten the rear chain/s by hand as snug as you can, then get on the tractor and pull forward to tighten the rear chain/s. Set the brakes and dump the loader bucket just a bit (while it's at rest on the trailer bed). The lip of the bucket will press on the trailer bed and this will take a bit of weight off the front wheels. Then hand-tighten the front chains to your chain hooks which of course have been thoughtfully welded on the top edge of the loader bucket. Then slowly rotate the bucket back to snug everything up. Shut'er down and leave with brakes set and in gear. This tightens everything with tractor power (no pesky binders to loosen up) and if the loader hydraulics tend to leak down, the effect is to tighten the load rather than loosen it. Run all chains to the attachment points on the sides of your trailer (you gotta have them - if you don't, get beefy ones welded on). If possible, fasten the chains to the side rails of your trailer so that if a weld breaks, the chain has something else to catch on before it becomes totally unhitched (i.e. front side of a stake pocket). Drop the chain hook down over the stake pocket so gravity keeps it connected, and then bring the chain up through the stake pocket. Front chains should run a couple of feet forward of their tractor attachment points, and rear chains should run a couple of feet aft. If you're hauling long distance, wooden 4x4 (6x6 is better!) blocks nailed to the trailer floor offer good peace of mind (in front of the rear tires and in back of the front tires). Don't scrimp on chains, and for goodness sake observe all the weight limitations of your trailer, towing vehicle, ball, coupler, etc. Check everything after just a few miles, since initial weight shifting will probably show up in loosened chains sooner rather than later. Make plenty of rest stops and check your tie-downs, tires (heat) and wheel bearings (heat) regularly. Keep good tires on the ground and keep the tire pressures up to the maximum rated for the tire to ensure cool running and don't overload the tires anywhere in your rig. A flat at 60 mph and 15,000 lbs GCVW is no joke. You should know your empty pickup's weight, your empty trailer's weight and the weight of your load. Then take your empty pickup to a place where they move weight around easily (feed store, ag supplies, etc.) and get someone with a forklift to put your pickup's rated payload (a complex number, and smaller than you might think) in the form of a pallet-load of fertilizer, etc.right over your hitch point, which is the rear axle if you pull gooseneck. If you use a frame hitch with ball insert, put the rated maximum trailer tongue load directly over the ball, which means somewhere on the rear bed/open tailgate. In either case, measure at the rear bumper how much squat you get in inches at the rated load, and compare it to the bumper height with no load. The difference (for example, four inches of squat for 2000 lb payload over the rear axle in an F250 diesel) shows you how much your pickup should squat at its rated load. This gives you a way to determine if you've properly loaded your trailer based on its weight, the weight of your equipment (cargo) and the towing capacity of your pickup's trailering setup. This isn't the whole story, since none of the numbers can be exceeded, but I've found it a good way to make sure I'm getting as much weight as possible onto the towing vehicle without overloading it (to prevent deadly oscillations, mentioned in other posts here). If you know all your other weights, you should be able to determine if you've got the weight you need on the hitch-point (10-15% of the total trailer load for frame/ball mount hitches and larger amounts, depending on the trailer, for the gooseneck setup). You probably shouldn't be hauling around anything bigger than a lawn tractor unless you have a trailer with brakes. Good luck, make sure all your lights work, and be careful.
