How to Select a Trailer Hitch
Classes, receiver sizes, and matching hitch ratings to the trailer.
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A plug tester shows which circuits are live at the vehicle or trailer connector. Use it before you replace lamps or harnesses so you stop guessing.

Plug the tester into the vehicle socket, then step on brakes and signal. Lights on the tester should match. Repeat at the trailer plug if you have an adapter for that test.
Dark pins point upstream to fuses and grounds. Good vehicle pins with dark trailer lamps point at the trailer harness. Keep a tester in the glovebox for Canadian roadside surprises.
Confirm ratings and fit notes on each product page before you order.


Official clips from @curtmfg. If an embed stalls, use the YouTube link under the video.
Classes, receiver sizes, and matching hitch ratings to the trailer.
Watch on YouTube