4-Way to 5-Way Adapter for 2025 Toyota Highlander towing Boat Trailer
Updated 08/15/2025 | Published 07/22/2025
Question:
I have a 2025 Toyota Highlander with a factory installed tow package and a 4 pole connector. My boat trailer has a 5 pole connector. Is their a wiring harness that I can purchase that addresses this difference
asked by: Richard M
0
Expert Reply:
Hey Richard, what you'd need is a 4-way to 5-way adapter like the part # 20036 which you'd need to run the extra wire to your Highlander's reverse light circuit so that your trailer will be able to back up without the surge brakes applying.
expert reply by:
Jameson C
0
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Jameson C.
8/15/2025
Hey Richard, did you get a chance to try out the 4-way to 5-way adapter for your Highlander and boat trailer? I'm curious to know if it solved the issue with your trailer's surge brakes. Let me know how it worked out, as it could really help others facing the same challenge!