Desert Captain wrote:
...there should be nothing further needed except getting the rig weighed and your tires properly inflated for the load they are actually carrying...
...A trip to the Cat Scale and worst case perhaps having the alignment re done should solve all of the OP's problems...
If you have an '06 coach, or an E450 older than 2008, your front axle rating is 4600 pounds. That's max, and 65 PSI will carry that load. Less than 4600 ==> Less than 65. The trip to the CAT scale and adjustment of front tire pressure accordingly is ESSENTIAL.
Here's
A Weight-to-Pressure Chart. You probably have 225/75R16E tires. Say you find your front axle weight is 4100. In the chart, 2060x2 is 4120, and 55 PSI carries that weight. OK, your tires are hot, so set pressure to 60 and go try it. Next time they're cold, set to 55, 57, no more than 60. The Fords get very twitchy if the front tires are over-inflated. If some tire jockey inflated all six new tires to the 80 PSI max on the sidewalls, handling will be atrocious. That happened to me. I specified 65 front, they did 80, and it was just that...atrocious.