Agree on the carbon pile tester, only true way to test load capability and condition of a battery.
In his (daytona701) case, it could be a bad or loose internal cell connector causing the problem and a electronic tester will not adequately test it for that issue.
As to batteries:
Most aftermarket car batteries sold in the U.S. are made by just three big companies that build them for retailers: Johnson Controls, which supplies more than half of the market; Exide; and East Penn. There are other smaller ones, but these are the big three.
Interstate batteries are made by multiple suppliers, with Clarios and Exide Technologies being the most likely.
Kirkland automotive batteries (formerly sold at Costco) were made by Johnson Controls.
ODYSSEY® batteries are manufactured by EnerSys Energy Products Inc.
American made in Warrensburg, Missouri, the largest industrial commercial battery manufacturer in the world.
Personally I liked the NorthStar Batteries and have several of them, but they were bought out and absorbed by EnerSys to limit competition.
My next battery will be an Odyssey/EnerSys unless something better comes along in the future.
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Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited
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