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For trailer brake wiring, I highly recommend thick 10 gauge wiring (ouside the axle) and its install using STAR design (instead of usual linear design).
re:
- Linear Design / factory default - - much better STAR design - - Inner Hub area under my utility trailer - - inner hub area under my boat trailer - If STAR design is installed and still doesn't grab "like it should", remove each brake drum hub and "clean" the drum's contact area using brake cleaner spray. Some brake drum companies apply a thin coat of oil on brake drum's PAD area to reduce rust. Always clean this inner side contact area before installing on axle's hub. Many folks forget this cleaning step.
Hope this helps.
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