Data sources
Every vehicle figure on this site comes from the manufacturer's own published material for that model year, and each vehicle page names and links its source.
What we use
- Manufacturer towing guides. Yearly towing guides and towing charts published by the vehicle maker. These are our main source.
- Owner's manuals and spec sheets from the maker, where the towing guide does not cover a figure.
We do not use dealer listings, forums or other towing websites as a source for numbers.
How we check
- We download the original document and keep a copy of it. If the maker's download server blocks automated tools, we take the same document from the Internet Archive's stored copy of the maker's own address, and still link to the maker's address.
- We extract the tables and match each row to an engine, cab, bed, drive and axle combination.
- Each table is transcribed twice, independently, and the two versions are compared number by number; every figure is then matched against the document's own text. Rows we cannot match with certainty are left out rather than guessed.
- Each vehicle page shows the source document and the date we last checked it.