First things first, get yourself a good tire gauge that is trust worthy and throw it into your trailer toolbox, you'll always need it. (
https://www.homedepot.com/p/VIAIR-2-...0072/202948498 ) I highly doubt that your sway is caused by over pressure or out of balance, but perhaps something else is going on, is trailer sitting level, not enough weight on tongue, do you have a sway bar or sway control not set properly, a bent trailer axle from maybe driving over a curb. Somethings just not adding up unfortunately. When I added our Endurance (balanced) it went FROM sway and bounce, to completely straight and a beautiful towing experience. I added the sway bar to our Reese WD hitch just previous to installing tires but the biggest asset to the towing experience was the tires. Now it's sit back, relax and enjoy the scenery. Where before you just never knew what direction that trailer wanted to jump to.