A trailer tire's load rating is a hard component limit that deserves its own check. The useful number is the maximum load in pounds printed for the tire at its specified cold inflation pressure.
Estimate weight carried by the trailer tires
The trailer axles carry the loaded trailer weight that is not supported at the hitch. Divide that estimated axle-group load by the number of load-carrying trailer tires for a basic average per-tire load.
Real loading is not perfectly equal. Side-to-side cargo placement, road crown, suspension differences and tandem-axle geometry can create higher loads on individual tires.
Read the sidewall
Do not select a tire only because it says Load Range D or E. Compare the actual maximum load rating in pounds at the stated cold pressure, and follow the tire and trailer manufacturer's specifications.
Capacity is not the only tire concern
Inflation, age, condition, heat, speed, wheel rating and valve-stem capability all matter. A tire can fail for reasons that are not visible in a simple capacity calculation.
Frequently asked questions
Should I divide trailer GVWR by four for a tandem axle trailer?
That is a rough worst-case starting point, but some trailer weight is usually carried at the hitch and actual tire loads can be uneven. Use real loaded weights and component ratings for final checks.
Is more tire reserve always better?
Additional capacity can provide operating margin, but tire selection must remain compatible with the trailer, wheel, pressure and manufacturer requirements.