Replacing a CURT trailer-side 7-way RV blade cable starts with the plug style and actual wire length. The 56601–56603 numbers identify standard replacement leads, while 56621–56623 are retail-packaged versions. Cold-weather cables have their own part numbers and a more flexible outer jacket. Match the existing cable route and connector before replacing the lead.
Identify the right replacement format
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.
56621, 56622 and 56623 are CURT's packaged counterparts to the same three standard cable lengths. Packaging does not change the connector format.
56611 and 56613 have 6- and 10-foot soft thermoplastic elastomer jackets. CURT specifies a temperature range of -40°F to 221°F for these cold-weather models.
Identify CURT harnesses from the product number
A harness with longer cable does not change which connector it plugs into. Check that the old end is a 7-way RV blade and not a 7-pin round style.
| 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 |
| 56611 | 6 ft | Cold-weather | Standard | Male 7-way RV blade / trailer side |
The 6-foot cold-weather 56611 is listed here; it should not be substituted for a standard 56601 merely because both have six-foot leads.
Verify connector orientation and wire functions
Inspect the trailer cable for chafing, corrosion, frayed wires and water entry, then confirm cable routing allows full articulation when turning. Check individual circuits by function before joining conductors.
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.
Find the CURT replacement harness by exact MPN
Open the correct harness to review its listing and current availability.
CURT 56601
Six-foot trailer-side 7-way RV blade replacement lead with colour-coded wires and weather-resistant cable.
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CURT 56602
Eight-foot standard replacement lead for trailers needing more routing length than the 6-foot version.
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CURT 56603
Ten-foot standard replacement lead; check slack and wire routing before selecting.
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CURT 56621
Six-foot packaged counterpart to the standard 56601-style harness.
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CURT 56622
Eight-foot retail-packaged version of the standard trailer-side 7-way blade cable.
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CURT 56623
Ten-foot retail-packaged trailer-side replacement wiring harness.
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CURT 56613
Ten-foot cold-weather thermoplastic elastomer jacket rated from -40°F to 221°F by CURT.
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CURT 56611
Six-foot cold-weather thermoplastic elastomer jacket rated from -40°F to 221°F by CURT.
Check current listing and availabilityOther trailer connector identification
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