Weird problem, trailer sway and possible 5th wheel issue?

You’ve never driven a truck with 8 new tires before?

 

No, that tire has been SHAVED. If you'd been paying attention, that was already covered a few answers before you.

How true. Working for a mega-carrier I got hat a lot; usually dogging to the passenger side. Once, by nearly half a lane!
What happens is that sometimes a driver hits something really hard and smacks the trailer axles out of alignment. Road Service will get the bent rims and blown tires replaced, but in cases like these the trailer will always dog-track towards the side that got hit from ahead (hit an axle from behind, and the opposite is true).

 

Every time we get new drives there is a pucker incident the first time we get up to speed on the highway, especially if it's rutted.

 

On a new tire, especially one like yours with deep lugs, the lugs will flex until the tire gets broken in. Hauling a load with a high center of gravity, or livestock, or a tank like you are will exaggerate the feeling of the rear of the truck being loose. It doesn’t take long to go away. Maybe a week or two at most.

 

We used to carry a 5 gallon bucket of grease, now the shop ask why you need it.

 

Last time I drove for Inland I ask for grease and they gave me a new unopened 2.5 gallon buckey no questions ask.

 

Just a ding dang minute, nobody else saw this??? It looks like the air bags aren't properly inflated. For shame, and don't worry about those "things", those are shock absorbers and the outside cover always rusts, as long as not leaking, but really folks, don't you think improperly inflated air bags might cause a problem? Downright dangerous if loaded,,see, old truckers aren't so useless after all.