Tire pressures vs chart

You're not missing anything. 3200 lbs on the front axle is around 1/2 of what 2 load range e little tires like you have are rated for. Hence the 40 psi MINIMUM pressure for 16xx lbs per tire. (Rvnet number crunchers, I did not look this up, so don't not pick the fine print. I'm talking rough numbers)
As said, the door sticker is a "safe" all around pressure.
Nothing to worry about, however, I'd run 10 psi above the minimum calculated pressure to help with cornering/handling.

Don't worry though, the peanut gallery will try to help confuse the issue.

My casual observation is (assuming this is a class C camper) that the front end seems pretty light. Is there a bunch of weight aft, taking some weight off the front axle?

Cummins12V98 wrote:
I use the charts and add 5psi for rears and 10psi for fonts.

Same as you but reversed....my TC only adds 100lbs to the front axle. Empty I run 45psi.

Tire manufacture's charts are the maximum load for that pressure, not recommended pressures because they don't know what vehicle they will be mounted on. Vehicle manufacture settings are a compromise and take in account load, ride, handling and braking for that vehicle.

I like to have some extra load capacity in my pocket as well.

Cummins12V98 wrote:
I use the charts and add 5psi for rears and 10psi for fonts.

+1 unless there is a reason to run the absolute minimum.

Cummins12V98 wrote:

IAMICHABOD wrote:

Cummins12V98 wrote:
I use the charts and add 5psi for rears and 10psi for fonts.

Why do that? :?WAG would get the same results......

I have very specific reasons for doing so with several sets of tires making it to 100k and beyond.

Thanks for your constructive post!

What would be some of your specific reasons?

IAMICHABOD wrote:

Cummins12V98 wrote:
I use the charts and add 5psi for rears and 10psi for fonts.

Why do that? :?WAG would get the same results......

I have very specific reasons for doing so with several sets of tires making it to 100k and beyond.

Thanks for your constructive post!

Cummins12V98 wrote:
I use the charts and add 5psi for rears and 10psi for fonts.

Why do that? :?WAG would get the same results......

The door sticker usually assumes the maximum rated load for each axle (i.e. the GAWR). Ford doesn't know how you or the vehicle outfitter will be loading their chassis. If your front axle is lighter than the GAWR, then you can safely use a lower pressure as per the tire manufacturer's recommendations.

I use the charts and add 5psi for rears and 10psi for fonts.

Wrong chart.

Stick to the one specific for your truck and tires. This ain’t a one-size-fits-all situation.