About TowMargin
TowMargin helps U.S. RV and travel trailer users estimate margins from entered ratings and weights.
It focuses on payload first because tongue weight, passengers, cargo, hitch hardware, and accessories can use payload before tow rating becomes the limiting number.
What TowMargin does
TowMargin turns entered truck ratings, trailer weights, trip load, and tongue weight into a towing margin report.
The report is meant to help you see which entered rating is tightest and which source number should be checked next.
Methodology and example setup
TowMargin worksheet v2: entered ratings only, payload-first margin, report-first output, and no vehicle spec database.
Example setup: a 1,650 lb payload sticker, 590 lb of people/cargo/hitch load, and 845 lb of tongue weight leaves 215 lb of entered payload margin.
Verification order: use certified scale data when available; otherwise use labels, manuals, towing guides, receiver labels, and clearly marked estimates.
What TowMargin does not do
TowMargin does not maintain a vehicle spec database, look up payload from a VIN, certify a setup, or replace labels, manuals, towing guides, receiver labels, trailer labels, or certified scale readings.