It all depends on the GVWR and GAWRs of your Excel. Being a 2001 30 footer, I wouldn't be surprised if the 235/85R16E tire size was original to the OEM. If the tires are LT, my preferred replacement would be the all-steel construction, commercial service Michelin XPS Rib which is available as an LT235/85R16E. I've run these under a previous model year 2000 5th wheel with absolutely no tire problems.
If you want to stay with this tire size, you could theoretically move up to a tire such as the all-steel construction LT235/85R16G Goodyear G614 RST that's rated 3750 lbs @ 110 PSIG, a significant step up from the current tires that (if LT tires) are probably rated 3042 lbs @ 80 PSIG. Chances are you couldn't run the G614s at their full 110 PSIG inflation pressure without a wheel upgrade, however, as I doubt the 2001 wheels were rated for 110 PSIG.
Rusty