Yesterday morning I was about to leave home to go to the office and when I turned the key in the ignition of the Jeep Wrangler JKU, all I heard was a click and no start. I tapped a button on the sPOD touchpanel and it didn’t turn on indicating the battery was dead (definitely below 12V). I thought that was odd. I noticed that the passenger side door was not fully engaged, so I was guessing maybe the dome lights were on all night.
I pulled the NOCO Genius Boost HD GB70 jump starter from the back and was able to jump start the Wrangler.
While it was great to find out the NOCO GB70 actually works (never tested it), it was disconcerting that my battery was dead. I ended up heading to the office with a long idle at Starbucks waiting for my coffee, but when I got to the parking lot and killed the ignition and tried to restart, it still failed to start off battery.
At the end of the day, I jump started off the NOCO again and drove home. I took the battery out and used a battery charger and got it to 12.85V (voltmeter verified). Then I took it off the charger and let it sit for an hour and it dropped to 10.8V.
So after only 18 months of ownership (new Jeep Wrangler), the OEM battery died. I went online and there were lots of stories about premature OEM battery failure in Jeep Wranglers, but these stories were more in-line with 2-3 years of ownership.
I decided to skip another standard lead acid battery and go with an absorbent glass mat (AGM) battery with the Odyssey Extreme 34R-PC1500T AGM battery. The AGM batteries are 2-3x more expensive than traditional lead acid, but the benefit is longer service life, low self-discharge rate, good performance in low temperature, and no spilling of lead acid. The no-spill aspect is a great benefit for an off-road vehicle lead acid can be an issue when off-camber and/or driving on rough trails.
If you have a 2012 to 2018 Jeep Wrangler JK, be sure to note that you have to get a battery where the positive terminal is close to the bottom right corner (however the battery is oriented). If the positive terminal is closest to the left bottom/lower corner, the battery will not fit because of how the cables are setup in the 2012+ JK.
So if you buy an Odyssey Extreme battery, be sure to get the 34R and not the 34. The R in 34R means reversed terminal positions.
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