rb70383, I'm new to the forum and new to the party, might as well jump in with my 2 cents here.
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Best I figure the question really isn't what you should do it's what's ideal and where can you cut corners. Given that this is a recovery winch on what sounds like a heavy use rig I'd think it prudent to plan for the worse case. I'm also pretty sure I read or can assume that you have a large front winch plus the smaller bed winch. First real question to my mind is do you think it prudent to be able to run the winches(any of the 3) with the engine not running in case you need to recover the rig from a situation where the engine can't run, it's broken, under water, etc.? If the answer is yes then you absolutely should add a battery or two and wiring is different, this would allow you do drain down the winch battery while keeping the starting batteries charged. How a second battery/winch is connected is secondary to that question.
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Best I figure the question really isn't what you should do it's what's ideal and where can you cut corners. Given that this is a recovery winch on what sounds like a heavy use rig I'd think it prudent to plan for the worse case. I'm also pretty sure I read or can assume that you have a large front winch plus the smaller bed winch. First real question to my mind is do you think it prudent to be able to run the winches(any of the 3) with the engine not running in case you need to recover the rig from a situation where the engine can't run, it's broken, under water, etc.? If the answer is yes then you absolutely should add a battery or two and wiring is different, this would allow you do drain down the winch battery while keeping the starting batteries charged. How a second battery/winch is connected is secondary to that question.
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