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Curved fitting and straight fitting
A dual has two valve stems, and they do not sit in identical places relative to a bar across the hub. The film does not pretend one hose end fits both. One hose uses a curved fitting. The other uses a straight fitting. Each meets a valve stem. That is the connection that lets one wireless transmitter serve both tires: equalize pressure between them, and monitor low and high pressure.
Shops that have fought dual hoses know why the two shapes exist. One stem is easier to reach in a straight line. The other needs the hose to turn so it does not kink, rub, or load the stem sideways. A kinked hose is not equalization. It is a closed door between two tires that will drift apart the way they always have. Taking the extra minute to put the curved fitting on the stem that needs the curve is the install, not a flourish. The film’s five minutes a sensor includes that step.
Safety follows from the connection being real. If only one stem is attached, you do not have the dual the product is for. The unconnected tire is back to a gauge and a guess, and the connected tire is a single wearing a hose. The truck does not drive balanced because a bar is present. It drives balanced when the two tires can share pressure and the system can see low and high. Temperature still belongs to the cabin display, which stores the date and time of a temperature problem along with pressure problems.
Security is a connection a pre-trip can see. Stems, fittings, and hoses are visible unless you add the optional chrome hub cover. If you use the cover, the pre-trip has to include a look that the cover is seated and the hoses were not pinched when it went on. The handheld marks truck positions 1 through 6 and trailer positions 1 through 4 so a leaking fitting has a position name in the cab, not “somewhere on the left.”
Value is a dual that stays a dual after the fitter leaves. The most expensive hose job is the one that is almost done: one fitting tight, one fitting “we’ll get it after lunch,” and a truck that rolls with half a system. Trailer installation is very similar, and trailer stems are where half-finished work hides. About forty minutes for the truck is the film’s figure for doing the positions, not for mounting a bar and calling it good.
The repeater still goes inside the steering-axle wheel. The receiver still goes in the cab, with power, mute, Pre-trip, and Learn. Antennas and the power lead are part of the kit in the box. The site says all-in-one and built in the USA. Those are site claims. The film shows curved and straight fittings in the install. A reading of 104 PSI and 53°F is one screen, not a fitting rating.
Every truck and every trailer needs both stems connected for safety, security, and value. When you write, say whether your duals are on tractors, trailers, or both. Someone replies about your trucks. If the form fails, use customersupport@truckstpms.com. Your typed note stays on the page.
Mark the hoses in your own shop if the curved and straight ends get mixed in a bin. The film is clear about which shape meets which kind of reach, and a straight fitting forced into a turn will crack a stem or unthread itself on the first hundred miles. Carry spare caps. A stem that loses its cap before the fitting goes on is a stem that arrives full of grit. Crack the valve only when the fitting is ready, so you are not bleeding the tire while you search the tray. On an inside dual, do the hard stem first, while you can still see it, and the easy stem second. Installers who do the easy stem first sometimes "come back" to the inside one after the truck is on the ground. That is how duals leave with one hose. One hose is not equalization.
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Every truck and every trailer needs the Greenbox for safety, security, and value. Send a note and someone replies about your trucks.