CURT Trailer 7-Way Replacement Harnesses: Length & Cold-Weather Guide

A damaged trailer-side 7-way RV blade plug can be replaced with a wired CURT pigtail harness instead of rewiring the entire trailer. CURT supplies standard 6-, 8- and 10-foot leads, retail-packaged counterparts and a cold-weather option. This guide compares exact model numbers so you can choose enough cable reach without confusing a trailer-side plug with a vehicle-side socket.

Cable length, packaging and cold-weather jacket

Standard 6–10 ft

56601, 56602 and 56603 have 6-, 8- and 10-foot weather-resistant cables. The trailer-side male RV blade connector is moulded to the harness.

Retail-packaged versions

56621, 56622 and 56623 are CURT's packaged counterparts to the same three standard cable lengths. Packaging does not change the connector format.

Cold-weather cable

56613 is the 10-foot cold-weather version available in this selection. CURT specifies a temperature range of -40°F to 221°F for these cold-weather models.

CURT trailer-side 7-way harness length comparison

These are trailer-side replacement leads: a moulded male RV blade plug at one end and colour-coded wires for splicing into existing trailer circuits at the other. They are not custom truck-bed extensions or vehicle-side connectors.

Manufacturer MPN Cable length Cable type Packaging Connector
56601 6 ft Standard Standard Male 7-way RV blade / trailer side
56602 8 ft Standard Standard Male 7-way RV blade / trailer side
56603 10 ft Standard Standard Male 7-way RV blade / trailer side
56621 6 ft Standard Retail-packaged Male 7-way RV blade / trailer side
56622 8 ft Standard Retail-packaged Male 7-way RV blade / trailer side
56623 10 ft Standard Retail-packaged Male 7-way RV blade / trailer side
56613 10 ft Cold-weather Standard Male 7-way RV blade / trailer side

The cold-weather 6-foot 56611 is a separate manufacturer model, but it is not part of this store's linked product selection.

Splicing and installation checks

Allow sufficient cable length for steering turns and trailer articulation without leaving a dragging loop. Protect splices against moisture, support the cable away from sharp edges, and test brakes, turn signals, running lights, reverse-light and auxiliary circuits as applicable.

Traditional and SAE RV-blade colours can differ

CURT documents both traditional and SAE J2863 7-way RV blade colour/function arrangements. Verify the individual pin functions against the trailer's actual wiring rather than joining same-colour wires without testing. Disconnect electrical power before splicing and follow the connector installation instructions.

Some trailers use a 7-way round-pin connector rather than an RV blade connector. The pin and socket shapes differ and are not interchangeable.

CURT 7-way RV blade trailer-side replacement leads

Select the correct cable type and length below to see product details and availability.

Related trailer wiring references

CURT 7-way plug/socket wiring and connector types

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