Many high end aluminum wheels like Alcoa (others) are built for higher load and pressure numbers for that size wheel. They tell us the valve stem dictates pressures. Don't assume all aluminum trailer wheels are the same....their not.
Other aluminum off shore brand trailer wheels can have different load and psi ratings.
Many Older steel wheels carried different load and psi ratings vs todays newer gen steel wheels may carry the max load/psi rating for common tire in that size and load range.
be safe out there...ask the mfg/wheel dealer first