smooth move

had a problem last week with the winch pulling the battery down, even with the motor running. was wondering about going to a 2 battery system, with the winch wired to the 2nd batt. anyone do this or have any info, thanks

DortDizzle

Winches pull a lot of current! Two batteries would help and its on my list but its a system problem. Your alternator only puts out about 100amps max. Full load currents can be in the 900amps range depending on the winch. Two batteries can extend the capacity before running down but that energy has to be put back in by your alternator.

Dual batteries awesome. Allows more capacity and takes some strain off the alt for heavy pulls. Will you be able to pull full load forever without voltage droop. No. Will a higher capacity alt help, yes. Will you find a 1000 amp alt? Probably not.

Your on the right path for beefing up your elecical system. This will allow for longer pulls before taking a break to let your system recharge.

Also alternator output increases with RPM so give some gas while pulling.

BlackMambaXJ

I'm curious as to how the wiring would be done to add a second battery?

investinwaffles

I would say dual batteries would help more in this situation than an upgraded alternator would. Obviously both would be the ideal combo.

I don't have a winch, but I personally don't need one on the regular, and those long and draining pulls even less frequently. A stock alternator will only charge a little slower than a higher amp unit in this situation, as neither will be able to keep up with the current draw.

Still, at the very least go grab a 136amp unit out of a ZJ/Durango or what have you, and have it rebuilt. Only cost me $20 (junkyard) + 75 for the rebuild and it didn't take much grinding to drop it in place.

I really want to put another battery where the factory air-box is on my 98,opposite to the factory battery location, but I have seen claims that it will bend the unibody (though it's only 40 or so lbs...)

96blackxj

im going to put another battery inside my jeep when i get ready to add some lights to the front it always helps to have 2 batteries cant go wrong

what im going to do is put a battery tray in the back, run a 2 gauge wire from the front battery positive to the back battery positive and run a 2 guage wire from the back battery negative to a ground somewhere close...

also im going to put 80amp inline fuse at both ends at the main battery and one at the secondary battery in case something just happens to short out there is no electrical fire

andrewmp6

Blackmambaxj http://www.jeep4x4center.com/rugged-...relay-kit.html and drivers side battery tray http://www.quadratec.com/products/17004_719.htm

SeriousOffroad

Here ya go...
http://www.seriousoffroadproducts.co...-Power-Manager

SteveMongr

A deep cycle battery might be your best bet.
Works great for me.

ihscoutlover

I have seen this done several ways, and anyone with this also can chime in. The dual tray for the XJ holds two odessey batteries side by side, and has the isolator and wiring. The alternator only puts out 100-110amps max, and that is around the 2k rpm range. Mean Green makes some aftermarket alternators, but the real key here is for a winch application to match the winch close to what you have, at least the amp draw and capacity. A 8k to 9.5k winch is more than enough, but you need to read the amp pull specs at full capacity. Since the voltage regulation on the XJ's and I believe the ZJs and TJs are all done by the PCM, and the stock alts don't put out much, you are left to put in some kind of battery addition, or even run a second alternator, which I have also seen done. The OEM wiring is also smaller than intended for the job of aftermarket winches and such, so plan to rerun new higher gauge(lower number) wiring to and from the alternators and batteries, to get maximum effect, as well as pick or choose additional grounding points as well. There are plenty of kits available, like what Serious Off Road posted up. Deep cycle batteries are also what you need to be running, as they can recover better from being totally discharged, and being discharged heavily. There are some writeups on this subject here and on the NAXJA site. Painless makes good stuff, and I think they even have a Mil-Spec setup that is like totally waterproof, but don't hold me to that. Let us know what you find, and post up pics of what you come up with.

Jeff

wrapstar

A factory battery tray will fit on the drivers side if you remount the ecm. I dont have any pics on this phone but I've shown my setup before if you cant find it I can take some later and explain it.

smooth move

thanks for the replies. why do i need anything but another batt and the cable? my dodge/cummins truck has 2 batts and only the wiring. no switches or solinoids. i was going to weld another tray into the fender well and run short(12") cables. i've had this winch for 7 or 8 years and never had a problem during short term usage. i'm wondering if the winch motor is malfunctioning? never ends, does it?

tobtech

Technically all you need is the 2nd battery and cables BUT if you go this route you need 2 identical batteries in the same condition (so buy them at the same time).

The reason behind the methods that isolate the batteries is so that one battery is dedicated to accessories and another dedicated to starting so you always have power to start the Jeep regardless of the accessory usage. There are several ways to isolate them and many threads about that.

Both ways work good and have pros and cons to each.

skife

if 40lbs is going to bend the unibody, you've got a huge rust problem.

mbcazure

I like the advice going out in this thread. What about installing the Hi-idle switch modification? would that help with this issue at all? i have not installed a winch yet but i am interested for when I do...

Demonoid369

Best way to go is to upgrade the wiring for your battery/starter/alternator. Upgrade the alternator to at least a 120amp, the a second deep cycle battery. Plus a high idle switch would and could help a lot to keep the juices flowing to the battery. If not a smaller alt. pulley could work but then you run the risk of it burning out sooner since it'll always be turning faster.