sway

Who follows the door sticker for tire inflation, especially for non-OEM tires? I put in the max cold PSI indicated on the sidewall.

afidel wrote:
He has E rated tires, they certainly aren't passenger tires!

And E rating is not "stock" for that truck.

If OP is following inflation chart on the truck door post and is running LT tires rated for E loads, that chart is invalid as it will give them too low of a pressure.

That truck was equipped with PASSENGER tires and as such will have typical passenger tire pressures.

The tires in E rating will require MORE pressure than P tires to get the same weight rating or higher than P tires.

E rating tires to get max rated capacity are rated at 80 PSI, Passenger tires typically will max out at 35-36 PSI..

35 PSI in LT E rated tires would be considered as having a flat tire..

Too little air pressure in those E rated tires can easily give you an odd feeling of being pushed around..

OP should have gone with LT tires with C rating which would have given them some extra weight capacity over stock P tires and would be a much better match to the vehicle.

E capacity is too much overkill and potentially part of the problem they are having. And yes, you CAN have overkill on tires.

He has E rated tires, they certainly aren't passenger tires!

OP, be more specific. The fact that you mention it’s your “first trailer” and that it’s a good size trailer for a half ton, it could just be that your expectations aren’t in line with what it feels like to tow a trailer, or it could need some fine tuning.
Could be trailer is a bit light on the tongue and/or a lot of weight aft of the axles causing it to wag the dog a bit. Could be soft tires on the truck, could be not enough weight transfer and steering is light.....
Some expect a trailer to tow like it’s “not there.” Maybe a minor issue or 2 maybe nothing.
Some will say it’s too much trailer for the truck. I can tell you definitively, while it may be too much for some people, it is absolutely NOT too long or heavy for a new half ton. Not in the least. Difference in opinion, I know, but after 30 years of towing probably 100s or different trailers with dozens of different trucks of all sizes, it’s fine.
Some specifics could help dial it in or confirm its just normal behavior.

I agree about max pressure with P tires

It appears you have a TV and WDH that can handle your TT.
Go over the set up procedure for your WDH. It seems something may be off there.
I am one who recommends pumping up your TT and TV tires to their maximum sidewall pressure when towing to prevent any tire squirming. Makes a big difference with P tires.

Does this sway happen when no other traffic is around and no wind? Tread squirm and light suspension can cause your rig to waller around in your lane. If it only happens when other traffic is passing or mild crosswinds, but then straightens out, it’s likely normal reaction with a lightweight truck. I tow our 32.5’ TT with no sway control with our F250. Tows like a champ but we occasionally feel passing trucks. Box trucks are the worst as bow wave pushes while vacuum pulls the rear as they pass. Nothing scary but it’ll keep you awake. If you’re having sway as in oscillation above 45mph with no wind or traffic around, then I’d say tongue weight or too much hanging from the rear of the trailer. Some trailers tow better than others as well. Short wheelbase trailers are worse. Too much WD Trying to compensate for not enough truck can induce some steering disturbances as well. Been there too many years ago.

With a hitch with built in sway control, the set up is a huge part of your safety. Riding "level" is indeed a goal but consider this. You can raise you ball high enough to get it to ride level without putting any friction on your bars. I have an Equalizer hitch and they have some specific steps to follow. Mine is level but, that requires some pressure through the bars. If I had to add more pressure from the bars, then there would be other issues. Read the directions for your hitch and follow them for the initial set up. Call the manufacturer for more specific info.

You are maxing your F150. New truck needs to be at least an F250.
Forget the “dry” weight. Useless.
Glad you have new tires but tires don’t affect sway.
Air bags level the truck. Nothing else.
Your “bit” of reading isn’t sufficient.

I'd start by adding tongue weight. I'm pulling a 28' trailer with a gross weight of 7600lbs but it only weighs 6000. I'm putting 900lbs on the tongue and it pulls great even in cross winds. I also return the front wheel well height back to 90% of the starting measurement.