Hitch Cargo Carrier Weight Limit Calculator

The calculator

As an Amazon Associate I earn from qualifying purchases. The Amazon column links to an exact listing only where we have confirmed the model, and otherwise to a search for that model.

CURT, Understanding Towing (hitch class glossary, page 11)

The formula and its assumptions

For each tongue-weight limit, the cargo allowance is the limit minus the empty carrier’s weight:

cargo allowance = tongue-weight limit − empty carrier weight

The calculator works that out for the vehicle limit, the receiver rating and the extender rating (if you pick one). It then compares them with the carrier maker’s own load rating, which is already a cargo figure. The smallest of those numbers is your allowance, and the limit behind it is the one that binds.

Assumptions, stated plainly:

• All weight sits on the hitch as tongue weight. A cargo carrier hangs behind the receiver, so its weight and its load both count against the tongue-weight limits.
• The receiver class figures are the class maximums published by CURT. A given hitch can be rated lower, and its label is what counts. Choose “Other” and enter the label value if yours is lower.
• An extender or riser is limited by the tongue-weight rating its maker publishes. We list only the CURT extenders whose pages state a rating. We do not apply any other derating of our own, and none appears in the maker data we checked, except the StowAway2 rule below. If your extender is not listed, enter its maker’s rating, or do not use it.
• Where a maker does not publish an empty carrier weight, the calculator asks you to weigh the carrier and type it in. A shipping weight is not an empty weight, because it includes packaging.
• Dynamic loads on bumps can exceed the static weight. The ratings used here are the makers’ published ratings, not a prediction of what a rough road does.

Never exceed any rating. If the calculator shows a negative or zero allowance, that setup is not usable.

Extender and riser rules the makers publish

• CURT lists a tongue-weight rating of 350 lb for each of its receiver tube extenders and adapters in the table above. That rating, not your hitch’s, is the limit once the extender is in the line.
• StowAway2 says its Standard Cargo Carrier is designed for vehicles with a minimum 350 lb tongue weight capacity, and that a 7 in hitch extender may be used only with Class 3 or 4 hitches rated for more than 500 lb tongue weight (StowAway2 ).
• Yakima says the EXO SwingBase fits 2 in Class 3 and 4 receivers only, and gives different gear limits depending on whether the TopShelf is installed (Yakima ).

A worked example (made-up vehicle)

Suppose an owner’s manual gives a tongue-weight limit of 350 lb, the hitch is Class III (800 lb class maximum) and the carrier is a Yakima EXO GearWarrior on a SwingBase (90.5 lb together, 250 lb gear limit):

• Vehicle: 350 − 90.5 = 259.5 lb of cargo
• Receiver: 800 − 90.5 = 709.5 lb of cargo
• Carrier maker: 250 lb of cargo

The lowest is 250 lb, so the carrier’s own gear limit binds. With a 300 lb vehicle limit instead, the vehicle would bind at 209.5 lb. The vehicle numbers here are invented to show the method; they are not a real vehicle.

What this page does not cover

• Carriers whose makers do not publish a load rating on their product pages are left out (for example the Thule Arcos platforms, which list no rating).
• We could not read the StowAway2 page in a plain download, so its figures were read with a page-reading tool and are the ones to confirm against the maker’s page before you rely on them.
• Trailer towing is a separate calculation. This page is only about hitch-mounted cargo carriers.

For clearance, bumper and ground fit, see the hitch cargo carrier clearance guide . For carrier picks, see our hitch cargo carrier roundup .

Sources

• CURT, Understanding Towing (hitch class glossary)
• CURT cargo carrier and extender product pages , each linked in the tables
• Thule Arcos hitch cargo carriers
• Yakima EXO GearLocker , GearWarrior , SwingBase and TopShelf
• StowAway2 Standard Cargo Carrier
• MaxxHaul hitch cargo carriers