I am going to install a Smittybuilt 10,000 pound X2 winch on my XJ, do I need to install a 2nd battery ?

If so where is a good place to put it?

Thanks and have a Wonderful Day

Is there room to remove the airbox and add a battery there? You'd just have to re-route the intake tube and do a cowl intake or something.... Which, may not be a bad idea considering your adding a huge winch for some quality off road use and the possibility of crossing water holes...If you wanted a snorkel, just run the tube through the cowl area then out the side and into a snorkel.

A good single AGM battery would be sufficient for a consumer grade winch.

Adding a second battery wouldn't hurt if you really want one. But not absolutely necessary.

That winch does not have the amp draw of say a Warn of the same size. I think a smarter upgrade if you want to do one is the AGM battery and a higher amp alternator and late the alternator provide the lions share of the load

I have a 10K Smittybilt and it does fine with a single 65 size battery and 136 amp alternator.

Winches draw 3-400 amps at least. Cheap winches are worse. There's no way the alternator is taking the lion's share of that load. A good battery is vital when winching. A good alternator will take a little of the load but most of the load is handled by the battery. The good alternator will also top off the battery faster after you're done.

A good AGM battery will handle 700 amps with no problem.

So then I would say figure out what alternator you want to put in your XJ by reading the "junkyard parts" sticky, then get an AGM (absorbent glass mat) battery, and upgrade your cables to carry the load without getting hot, and be on your way!!!

I am going to disagree on that. I have a 250 amp alternator, minus the 50 amps to run the ECM, which will handle the lions share of that 300 amps. Also in winches the line speed is the determining factor. The winches like a Warn are geared higher and will pull the line much faster with no load. However when they pull down, they will pull a good 700 amps. I have a Mile Marker 9K also that will pull for a good 30 minutes off a stock alternator (pulling multiple rigs up a hill) I have the vid to prove it. That was done on a regular battery and stock alternator. Eventually cooked the solenoids on that one.

So you are applying your special case with an alternator that has at least 2x the capacity of a stock XJ alternator to the general use case? And then you pick the low end 300A threshold to make your case when most winches are well above that threshold? Makes perfect sense...

Where are you getting your information? All of the documentation I see on Warn winches shows them all coming in between 4-500 amps under full load, just like all but the worst of the cheap winches.

You do realize that while you're unspooling your cable to run down to the next Jeep, the alternator is recharging the battery, don't you?

The information comes from a test done by one of the major off road magazines, Four Wheeler I think, who tested winches to failure. Results were surprising. No Warn was not the winner. Superwinch was. They also tested amp draw. There is a reason there is a difference in cable size required for the Mile Marker and Warn. So, OK, 200 amps is still a sizable share of the 400 amps you cite. Those alternators are also available for Chrysler products too. Just not a wrecking yard item as advocated by most here. I am not going to have some big internet argument about this. I chose this route for a reason, and a few not stated in this series. But I think you will have to concede there is nothing wrong with 250 amps when winching

I never said there was anything wrong with your setup.

Just that it has absolutely nothing to do with what one would recommend for the average XJ driver.

I can cite multiple sources showing instrumented tests of the amp draw of the various winches. If you're referring to the Four Wheeler test where they depleted the Optima Blue Top, that was a one off test and there's no way to know because they never measured amp draw. There's no way to know if they didn't have it fully charged when they started (which could very well have happened unintentionally). But even so, it still won first place in the shoot out in that article.

As far as I know it won't require the dual one to run a winch in your jeep- but it's a good idea to make sure you have plenty of reserve capacity in case you need to use thewinchfor long pulls or multiple uses in a short period of time.

Hmm. "Upgrade your cables", he says.

Which ones? A lot of off-roaders make the mistake of thinking they need big, fat, 00 cables everywhere if they have a winch.

Hogwash. You need bigger cables where you are running bigger current. That's not everywhere. So, where do you NOT need bigger cables?

1. Battery + to starter. Your starter isn't suddenly going to start pulling massive amperage because you installed a winch. In fact, in several major surveys, 100% of starters who took the survey weren't even aware that a winch had been installed, and didn't care, either.
2. Battery + to PDC. Same deal. No change in current flow.
3. Battery - to engine block ground. See above. The winch isn't going to change anything here.

Now, what about the others? Depends on what you are doing. Let's take a look:

1. Battery - to fender. Yeah, I'd bump this up a notch. No, you do NOT need 00 cable here! One gauge up, and do a much better job of attaching it to the fender. That fender ground is pathetic. Use a 5/16" bolt instead. I need to do a write-up on that.
2. Alternator to battery +. Yes, IF you install a bigger alternator. Again, not 00 or some craziness! It's a very short run - it does not need massive cable. 4 gauge is PLENTY for a 250 amp alternator. It's overkill, actually. 4 gauge will handle 250 amps for almost 2 meters @ 3% voltage drop. You are only going about a foot.

Of course, this is assuming that you will run separate power and ground cables to the winch from the battery.

Always use a ****** block. 1/2 the load on the winch. Twice the pull.