Little things

Like how I get nervous changing lanes to the right when the road is curving to the left, and vice versa.

See, when you turn one of these trucks, the tractor is no longer directly in front of the trailer. Which means that, on one side, the trailer is now blocking your view of the lane beside and behind you. Moving into that lane is now a matter of hoping nobody's moved into your new blind spot. Such fun.
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Like the art of staying in the center of the road. When the driver's seat isn't anywhere near the center of the truck.

When my father was teaching me how to drive, back in the Silurian Epoch, he used to get on my case about that. Called me a "mailbox driver." I kept trying to put myself in the middle of the lane. And most of the car was to my right. People walking on the shoulder of the highway would have been nervous, I suppose.

I had to learn that all over in these vehicles. They're wider even than the Pontiac dreadnoughts I learned to drive so long ago. I have to consciously remember that my seat is supposed to be near the centerline.

And that's before I check the mirrors to see where my trailer wheels are.
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Like rubber rubbing on steel.

That's what made me think of this today. I heard a faint noise during my pre-trip inspection and started poking around at the back of the cab. And found where some nameless mechanic had cable-tied the trailer air lines to the frame of the cab, in such a way that they were constantly rubbing against the sharp edge of a steel mounting block. I was able to patch the hole well enough to keep it drivable (at least until I could get to a shop), but if I hadn't noticed...

As you may have figured out by now, there aren't a lot of little things on one of these trucks.