Jeepin'_Aint_EZ

170 Watts would total 14.16 amps. Add that to 4.3L_XJ's high estimate of the jeep needing approx 100 amps with all factory accessories running and you get 114.16 amps. The grand cherokee alternator would be more than enough for you. Switch those lights out for LED's and you'll drop the amperage demand. And again, I stress the importance of a good/healthy battery as well.

Edit: 55 x 3 = 165 watts
35 x 2 = 70 watts
-------------------------------
235 watts total.

That would be 19.58 amps. Still good to use the grand cherokee alternator.

Ironside93

the battery in the jeep is a month old and it is a napa gold (?) battery with i believe 875 CCA. Do you think the stock alternator will work for the time being?

Jeepin'_Aint_EZ

Absolutely. I've winched completely stuck rigs at night with my auxiliary lights on using a yellow top optima and the factory alternator in my xj. And let me tell you this, a winch pulls much more amperage than your entire jeep does with a few lights on it lol. I hold her at about 2500-3k RPM for peak alternator output. These lights won't cause you any issues unless you're alternator isn't up to snuff which can be found with a load test. Local advance auto/ autozones perform the damn tests for free lol.

And for giggles, my milemarker winch draws 370 amps @12v under maximum of 8k pound load. Even a 2k pound load draws 175 amps. So I wouldn't be worried if I were you.

Ironside93

dude hell yeah! one last thing think you could drop by the frankenstein thread and drop in some advice for wiring or where to run the wiring? i would really appreciate it!

XJwonders

Don't forget to upgrade your cables when you do the alternator

Ironside93

Definitely! What gauge should I use?

BlueRidgeMark

Which cables?

I'm asking because a lot of people assume that they need to upgrade ALL cables when they run a higher amperage alternator. Not so. Where is that current going to run?

Let's start with where it's born - the alternator. Yep, an upgrade needed here. You are going to run more amperage from the alternator to the battery when you are in maximum draw mode. Go one, maybe two gauges up from stock. No, you don't need welding cable!

How about the stater cable? Nope. No real reason to touch it. It's not going to use one bit more than it has been. A stock cable is okay. (But 4 gauge is a nice upgrade.)

How about the ground cable? Oh, yeah. No question. That extra current has to get back to the battery. Upgrade at least the battery to fender cable (take it up to 6 gauge), but it wouldn't hurt to bump up the battery to block cable as well. Again, 4 gauge is a nice upgrade.

Not only the fender cable, but I'd make a better grounding point on the fender well itself. Take out that stupid sheet metal screw. Drill the hole out to accept a 5/16" bolt. Strip the paint down to bare metal around the hole. Now thread a stainless 5/16" bolt through from the backside. Put a good star washer on it first, and slop it up with dielectric grease. Once it's through, add a stainless flat washer, a stainless nut, and tighten it down good. Now you have a nice stud sticking out of the fenderwell. Add your new cable over that, and add another washer and nut. Now you have a FAR better grounding point for your Jeep.

There is at least one person on this forum who sells battery cable upgrade kits. I don't recall who it is, but a search should find him. IIRC, he does sell a 4 gauge kit (very nice), and a complete-waste-of-copper big fat 1/0 gauge kit. Also, you do NOT need a big fat cable on your head to firewall ground. That's a silly waste of money. It does nothing. That ground point is not intended to carry much current (picoamps), and the stock braid is plenty.

OR you can get some made at BestBoatWire.com, and get some military terminals to go with it all. I prefer military terminals to marine terminals (which are good) because they don't stick up as close to the hood and they provide two mounting points for cables. Either is a big improvement over stock, though.

Ironside93

Thanks for the awesome advice!

investinwaffles

Also to note is that XJ Wonders makes a custom battery cable kit for the XJ which is top notch. Professional grade crimps and heatshrink, I would have saved myself the hassle and just bought his if it was available when I redid my electrical cables

http://meanlemons.com

​​​​​I would buy his just to support another forum member and XJ enthisiast
​​​​​​

Ironside93

I'll definitely check in on the battery cable kit, and the wiring I'll definitely be bumping up to higher gauge wire.

BlueRidgeMark

Yeah, that's the guy I was thinking of. I chose to roll my own, but I have not heard anything but good about XJWonder's cables.

Just skip that firewall cable!

XJwonders

For the record. I don't make/use 1/0 cables. That's just ridiculous.

Ironside93

So what do you use / make

XJwonders

Either 4 gauge or 2 gauge.

Bugout4x4

The only time I have had demand issues is when I key up my radio... It better at least be running to keep up.