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Does anyone know what size the O ring is that goes between trans cooler line and radiator on a 2001 ford ranger 4.0? I recently put a new radiator on and now i cant get the cooler lines to stop leaking no matter what i do.I am wondering if possibly the new radiator has the wrong O rings in it and i cant compare to old one because i have already threw it away.Also, does the o ring sit between flare nut and line or between flared line and radiator? Any help would be greatly appreciated
Last edited by Loneranger2001; Apr 11, 2026 at 12:24 PM.
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