yes, it is not optimal but if the 12 volts are also flooded cell and not horrible old or something then it will be ok. If they are AGM or something then it will still work, but less than'ok', say ok-.
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Ford Explorer or Chrysler 300C to tow with.
Tracer Air 238 to be towed.
Triumph Thunderbird Sport - with the toy-hauler gone it's at home.
Retired very early and loving it.