Any leftover liquid is probably resting next to the black and grey shutoff valves just below the edge of the trailer. That's the low point in the system. I suppose if it freezes, expansion could break the plastic plumbing that houses the valves.
Would it be easy to take a bucket, open the cap and valves to drain out anything there? I think any small amount of stuff inside the tanks themselves would have plenty of room for expansion inside the tanks and be harmless.
Doug and Cheryl
2012 FC RB, Michelin 16, ProPride 1400
2016 Ram 1500 Laramie Crew Cab 4X4 Ecodiesel 3.92 axles
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