My first dually has been on order for nineteen days. Somewhere out there, a factory is building it, and I check the order status more than I check the weather.
Until it shows up, my older buddy Earl is letting me drive his. Loaded. With him in the passenger seat. His theory: you don't get to own one until you've learned on somebody else's. My theory: he wanted free help hauling his hay.
Earl has owned duallies for fifteen years. Long enough to know everything, he says. We'll see about that.
Five in the morning, flatbed loaded with hay, two gas station coffees filled right to the lid. I was driving, hands at ten and two, sweating like a kid at the DMV. Earl was riding shotgun like a sergeant supervising a bomb squad.
"Rule one," he said. "Nobody out there knows you're heavy. Nobody cares. Drive like every car around you is a raccoon with a driver's license. Plan three moves ahead."
I nodded like I understood. I did not.
First right turn of the day. I swung wide, the way you have to with a load behind you, and a little Prius saw that open space on the right and said, "That's mine." It shot into the gap like it was late for its own wedding.
I stood on the brakes. The truck stopped. The hay stopped. Earl's coffee did not stop. It went right into Earl's lap.
There was a long silence. Then Earl said, very calmly, "That's why we leave room. Priuses don't read."
Out on the highway, I started getting it. An SUV jumped lanes right in front of me and tapped its brakes, for no reason at all. But I'd already left a gap. Three moves ahead. Earl, damp but proud, gave me a slow nod.
That's when the dash chimed.
A little tire symbol lit up, and the screen showed one tire going low. Not a front. Not an outside rear. The inside rear on the left. The one tire you can't even see.
My heart hit the floor mat. "Is your truck dying?"
"No," Earl said. "That little TPMS sensor just earned its keep."
Here's what I learned, new folks. Your truck has TPMS — Tire Pressure Monitoring System. That's a small pressure sensor at the valve stem of each wheel. It watches the air and tattles when it drops. On a dually, that matters more than you think, because the inside rear tire hides behind the outside one. You'll never spot it low with your eyes. And if that inside tire runs low, the outside tire next to it ends up carrying the load for both. That's how one flat turns into two.
So we pulled into a truck stop and went hunting.
On a dually, the inside tire's valve stem lives at the bottom of a dark little canyon between the two rear wheels. I went in first. Fingers straight, no. Fingers sideways, no. I wedged my whole hand in there like I was fishing a quarter out of a couch and got stuck at the knuckles. Then I said a few words this newsletter won't print.
Earl watched the whole thing, wet jeans and all, with zero sympathy. "You done?"
Then he showed me the trick. You don't go between the wheels. You reach through the hole in the outside wheel, on the opposite side from the outside stem. He got down on one knee with his long-reach, dual-head gauge, the tool every dually owner should own, slid it straight through the hole, and hit the stem on the first try. And there it was. A tiny hiss.
The culprit was a rubber valve stem with a heavy metal extension hanging off it, flexing every mile like a diving board.
Earl stared at it for a while. "Fifteen years," he said. "Never once thought about what my stems were made of."
So here's the lesson for the old-timers, and yes, Earl, that means you. Those common rubber snap-in stems are rated to about 65 psi. Plenty of heavy duty pickup tires are Load Range E and can run up to 80. That's asking a lot of rubber. Metal clamp-in stems are built for that pressure. And if you run stem extensions, put them on metal stems only, never rubber. Metal clamp-in stems are the keepers. They stay on the wheel tire change after tire change, as long as the shop puts in a new seal, nut and core each time.
Earl aired it back up. We took it easy to a tire shop two exits down, the shop swapped in metal stems, and the light went off. Earl made me buy the next round of coffee. Lids on, this time.
On the drive home, I asked what pressure I should actually run. Sergeant Bomb Squad pointed at the sticker in the driver's door jamb. "That one. Not whatever the guy at the shop set it to in 2019. Check all six, inside ones too, and check them cold, before you roll."
Then he screwed a valve cap back on and tapped it. "And keep your caps on. They keep dirt and water out of the valve."