Best way to run power from truck battery to trailer winch. Quick disconnect ends.

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Grit dog

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Think about what Ricko is saying. It makes a big difference in what is the best and/or most economical or practical approach.
Couple times a year? First, don’t let the winch sit out in the weather or at least cover it from sun n rain.
Second? I wouldn’t even mess with all that. I’d just keep a deep cycle battery in a battery box,on a maintainer in the garage and bring it along and connect it to the winch as needed.
All the work and expense of making it plug n play seems to get lost if you only use it rarely. IMO.
 

Old Guy Bill

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I don’t know if this applies to where you keep your trailer but sometime in the near future I’ll be in the process of rigging up some kind of solar charger for my bosses dozer that sits outside…
 

HotWheelsBurban

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Think about what Ricko is saying. It makes a big difference in what is the best and/or most economical or practical approach.
Couple times a year? First, don’t let the winch sit out in the weather or at least cover it from sun n rain.
Second? I wouldn’t even mess with all that. I’d just keep a deep cycle battery in a battery box,on a maintainer in the garage and bring it along and connect it to the winch as needed.
All the work and expense of making it plug n play seems to get lost if you only use it rarely. IMO.
Buddy of mine used to pull the second battery out of his truck (Dodge Ram w/Cummins) and run his trailer winch with that. I can't recall if he had actual top post terminals on the wiring or just squeeze clamps. Probably the latter.... whatever it was, he made it work! And he hauled cars all over the South, so he used it frequently. He was a tight wallet country boy, and he didn't spend $$ if it wasn't absolutely necessary to.
 

Matt69olds

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I have a harbor freight 12k winch mounted on my trailer. I power it with the largest automotive battery that would fit in a battery box. I have the trailer wired to charge the battery whenever it plugged into the truck thru the 7 way plug.

As long as you have a good battery it should hold a charge for months.
 

RanchWelder

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Here's the Blue Sea Systems reference on wire gauge at amps:
https://d2pyqm2yd3fw2i.cloudfront.net/files/resources/reference/20010.pdf


Here's the rest of the Reference Library for alternative data and options for isolators:
https://www.bluesea.com/support/reference

You can download the catalog and the reference is included.
It's all copy written, so I did not post the charts.

Keep in mind, every battery is considered a DEEP Cell Marine using the Blue Sea charts and diagrams.

Every picture of a 250hp motor is another load, just like your portable welder, your winch, your 200 amp power inverter, your camper, you sewerage pump, etc.

There's diagrams for multi-battery with and without isolators and solar backup and solar charging options, for nearly every style of system you can imagine.

WARNE is $389 on sale for $311 directly from WARNE for the Truck side winch cables with isolator:
https://www.warn.com/quick-connect-power-cable-32966
(You can find it cheaper elsewhere, like ebay).

Here's the 90 inch extended cable for the trailer side:
https://www.warn.com/winch-quick-connect-power-cable-90-106077
 

Don-T

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I have an 8k Warn winch on my car trailer that is rarely used. When I do use it I don’t know what truck I will have so I do have a setup like you show with a good insulating sleeve over it. When I do use it, typically it is for a small tractor or a pickup truck with inflated tires so it is not a very hard pull. If the winch struggles enough to start warming up wires I just double the line pull. That has only happened one time.

If you can put a receiver on the front of your truck you can use a short power cable to help with the power loss.
 

bucket

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I have a harbor freight 12k winch mounted on my trailer. I power it with the largest automotive battery that would fit in a battery box. I have the trailer wired to charge the battery whenever it plugged into the truck thru the 7 way plug.

As long as you have a good battery it should hold a charge for months.

This is my preferred method as well. Simple and reliable. I've never found a need for an isolator on the aux wire. The winch should be used with the tow vehicle running anyhow.
 

Ricko1966

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The reason I was talking relay as an isolator was as a way to charge a trailer battery with the vehicle running on a 4 wire system, I suppose a person could run a single 12v source from battery to trailer,never thought about it. I think for the small expense involved and fairly easy install I'd still want to isolate the 2 batteries.
 

bucket

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The reason I was talking relay as an isolator was as a way to charge a trailer battery with the vehicle running on a 4 wire system, I suppose a person could run a single 12v source from battery to trailer,never thought about it. I think for the small expense involved and fairly easy install I'd still want to isolate the 2 batteries.

Honest question... is there anyone with a trailer big enough to utilize a winch that doesn't run a 7-pin connector anymore? I thought pretty much everyone has went to the 7-pin, which has the aux wire.
 

Ricko1966

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Honest question... is there anyone with a trailer big enough to utilize a winch that doesn't run a 7-pin connector anymore? I thought pretty much everyone has went to the 7-pin, which has the aux wire.
My trailer is big enough and 4 wire,but it's very old. Wow just realized it's gotta be 30 years old and my usual truck is almost 40.
 
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Nasty-LSX

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Ok, Thanks everyone for all your efforts in educating me with this. I guess I was overthinking
what I wanted. Good Idea, but not worth it. I only use this a couple times a year. It stays in storage.
Enclosed. I will just find a solar panel I can use to trickle the charge for the battery. Thanks again.

I got to use it today and just put another battery from one of the other c10's. The WARN winch is
BAD A$$.
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Hunter79764

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Just adding this if you have the battery, this ought to keep it charged, and they can live in the wild for a good number of years. We use them on deer feeders to keep batteries charged, and we easily get 7 or 8 years from them in central/west Texas sun. Pretty sure we have some much older than that, and they keep a battery alive for years with a 2-4x per day 5 second draw of a blower motor.
 

Fitz

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I use #2 gauge welding cable to run a "charge wire" to the rear off all my trucks. At the battery I make a short 10" cable. One 3/8" lug goes to the battery positive terminal. The other end gets a 1/4" lug. The 1/4" end goes to a 150 amp auto reset circuit breaker input stud. The cable going to the rear of the truck(s) is attached to the circuit breaker. It also gets a 1/4" lug on one end. And attaches to the 150 amp circuit breaker output stud. The end by the rear bumper gets a 3/8" lug. At the end of this cable will be a red colored female socket. The same ones used on a "cracker box" welder for the leads to be attached into. I buy all of the parts at a welding shop for each trailer that has a need for batteries to be recharged. Now, for hooking up to my different trailers for power. The rear of the cable, which is mounted into a 3/16"x3/16"x2" angle iron bracket. The angle iron bracket gets a hole in it large enough for the red female socket. This red female socket has a 3/8" stud on the back for the power cable. The angle iron bracket is either welded to the side of the 2" receiver on each truck. Or, it is drilled to be mounted using a couple of 5/16" bolts. The power cable and the female socket are then mounted into the hole in the angle iron bracket. A red male welding cable end is attached to more of the #2 gauge welding cable. The other end also receives a 3/8" lug. This last lug is attached to the positive battery terminal. I run two Group 31 batteries with studs, not post on my trailers. My trailers have 8,000 pound Ramsey DC-200 model winches on them. Have been using this set up for around 18 years. Hope that helps others in running power for trailers as well. Semper Fi. OUT!!!!!
 

Camar068

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Something like this and byor (buy your own wire).

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There’s pre-made winch cable kits as well. Presumably rated for the amp draw.
While it’s advisable to have the source nearer the load, ie, battery(s) on the trailer, for a seldom used device I can see the value of not having to maintain the extra battery(s) on the trailer.
Wish you were closer, I’d give you a new isolator and all the wiring for a 2nd under hood battery.
PO of the ‘77 C10 spent stupid $ to get it setup to power the old truck camper that his grampa originally had on the truck,just a couple years ago during Covid.
And then they used the camper like twice. He could rented a little tow behind for less money than he dumped into upgrades to the truck.
Anyway, I’d strongly consider an extra battery under hood whether you wire it up as a house only or added start battery.
You can calc the wire size needed for the winch. Look up the amp draw of the winch and use a wire size calculator. It’ll be substantial and the wire won’t be cheap. Likely 1/0 wire give r take a size.
Thats what I used on both ends of the wiring going to the wench in the bed.
 

Keith Seymore

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Think about what Ricko is saying. It makes a big difference in what is the best and/or most economical or practical approach.
Couple times a year? First, don’t let the winch sit out in the weather or at least cover it from sun n rain.
Second? I wouldn’t even mess with all that. I’d just keep a deep cycle battery in a battery box,on a maintainer in the garage and bring it along and connect it to the winch as needed.
All the work and expense of making it plug n play seems to get lost if you only use it rarely. IMO.
This is basically what I do.

There are two batteries in the race car. On the rare occasion I need to use the winch I take the easy battery out of the car and use that to run the winch.

K
 

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