Stock alternator or higher amp alternator?

Cbentz

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I finally got my Jeep running for the first time. After idling at 1k rmps for probably 5 minutes I noticed smoke coming from the alternator. Long story short the alternator was seized up. I'm just wondering if I should put a stock replacement one on it or go with more amps? If so which one should I look at purchasing? I am planning on building this Jeep and could use the extra amps.
 
Rarely are more amps needed or even ever used. A stock factory 117 amp alternator is all that's needed. Even if you have a winch. My TJ has all kinds of upgrades including a big AGM battery, winch, etc. yet I'm still happily running the OE 117 amp alternator.
 
Stick with the stock alternator. As Jerry said, no need for more amps.
 
if I should put a stock replacement one
Yes, it is a myth to think you need more amps. Most things we add which draw more amps are just momentary draws like a winch. Even extra lighting today tends to be low draw LED.
And loud after market stereos tend to much lower draw than the massive bass systems of 40 years ago.

The factory alternator is plenty. A bigger one is like putting a 16K winch on a TJ.
 
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Back in the day it was common to replace the stock jeep alternator with a higher amperage AC/Delco unit in order to better run high load accessories such as winches, but that was when the stock Jeep alternator was 63 amps (some of the earlier CJ-7's only had 45 amp alternators). The "high amperage replacement" was usually in the range of 100-105 amps except in rare cases where extremely high output was required as in the case of onboard welders.

At 117 amps you already have enough capacity for anything except a welder.
 
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The Durango alt that fits the 4.0 is 160amp. One extra mounting arm on the top needs to be cut off or it blocks the coil rail from maintainance.

Mine has been installed for several years. I put one in because at my old job I was jump starting old cold diesel trucks in the winter far more often than I should have been. Maybe it helped.
 
IMO the guys are right, the stocker is fine. However, since you are replacing it anyway, if it were me I would put in the Durango "upgrade." A solid unit from a junker should be fairly cheap.
 
Does anyone have a part number for the 117amp altenator? I need to replace mine on my 2.5 and all im finding are 75 and 90 amp models. And to confirm, the odessey battery is the way to go, right?
Thank you
 
I have two electric fans, a sub, seat heaters front and rear, and my stereo has its own amp as well. I'm very happy I went with a Durango alternator when my OEM unit died.
 
I don't think so anymore, they aren't what they used to be and they are spendy. I would look at an Interstate AGM
You've confused Odyssey with Optima. Odyssey is still superb, it was Optima whose reputation took a nosedive after they were purchased by Johnson Controls.
 
Im still running the stock 90 amp alternator. LED bulbs everywhere but the instrument cluster, LED rocklights, OBA compressor, ARB compressor, lighted psi gauge, winch, CB, heated seats, compass/temp mirror, 4 channel amp, and powered sub. Using an AGM battery and havent had any issues yet... Upgrading the alternator has been on the back of my mind though.
 
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