[JRTJH]

As Marshall posted, the issue is NOT the tire size but finding wheels to fit your lug pattern. Most 14" wheels are either 4 lug or 5 lug, 15" wheels are 5 lug or 6 lug and 16" wheels are 6 lug or 8 lug patterns.

So, assuming you currently have 14" 5 lug wheels, you'll find the only wheels that will fit your axles will be 14" (what you currently have) or 15" 5 lug wheels with the same lug pattern. None of the 16" wheels will fit your 5 lug pattern.

I'd suspect your current tire size is 205 75R14. If so, then your current tire diameter is 26.2". You could buy 15" 5 lug wheels and mount 225 75R15 tires which will have a diameter of around 28.3". That will be a total diameter increase of roughly 2.1" which equates to a radius height increase of roughly 1".

Assuming you want to upgrade wheels and tires, that is a very expensive project if the only purpose if to increase trailer height 1".

I wouldn't consider going this route if the only reason is to gain height. You're likely going to run into wheelwell clearance issues and possibly tire clearance issues (the spacing between the tires) as well.

Alternatives? Consider using a couple of 4' or 6' 2x8 or 2x10 boards as "flat ramps" to span the angle that's causing the problem. Or, possibly contact a trailer repair center near you. They can install 1" or 2" axle risers on the axle/U-bolt pads and accomplish the height rise without facing the clearance issues. Cost would probably be about half the price of new tires and wheels.