Overlanding

Dynamic roof load is the number that stops most builds

Vehicle manufacturers publish a dynamic roof load rating: the maximum weight the roof may carry while the vehicle is moving. On most crossovers and unibody SUVs it sits between 100 and 165 pounds, and it includes the rack, the crossbars and everything mounted to them. A 130-pound hardshell rooftop tent on a 165-pound-rated roof leaves 35 pounds for the rack — which most racks exceed on their own.

Static load, the weight the roof can hold while parked, is far higher because the suspension is not working and there are no cornering forces. That is the number that lets people sleep up there at all, and it is the number rooftop tent marketing quietly leans on. Both matter, and they are not interchangeable.

Find your vehicle's dynamic figure in the owner's manual, not on a forum, then subtract your rack's weight before you shop. On a lot of vehicles this arithmetic ends the rooftop tent conversation before it starts, and a ground tent turns out to be both cheaper and better.

Recovery gear is rated in a way that is easy to misread

A kinetic recovery rope and a tow strap are not the same thing and are not interchangeable. A kinetic rope is designed to stretch, storing energy and releasing it to pull a stuck vehicle out; a tow strap has minimal stretch and is for towing a rolling vehicle. Using a kinetic rope for towing, or a tow strap for a snatch recovery, is how equipment fails violently.

Minimum breaking strength should be roughly two to three times your vehicle's gross weight for a kinetic rope. Shackles need a working load limit that fits the same math, and — critically — they attach to rated recovery points, never to a tow ball or a trailer hitch's pin hole, which are not designed for shock loads.

Nobody should stand in the arc of a loaded strap. That one is free, it is universal, and it is the piece of advice most likely to matter on any given weekend.

Air and power are duty-cycle problems

An air compressor's rated CFM tells you how fast it moves air, but duty cycle tells you how long it can do so before it has to cool down. Airing four 33-inch tires back up from trail pressure is roughly fifteen to twenty minutes of continuous work, and a compressor with a 25 percent duty cycle at 100 PSI is going to make that a long afternoon.

Twelve-volt fridges are the same kind of problem with a different unit. Draw is quoted in amps at 12 volts, but a compressor fridge only runs perhaps a third of the time once cold, so real consumption sits somewhere around 0.5 to 1 amp-hour per hour in mild weather and climbs sharply in heat. Multiply by the hours you will be parked, compare that against your battery's usable capacity — half of a lead-acid battery's rated amp-hours, most of a lithium one's — and you will know whether you need a second battery before you need a bigger fridge.