After 10 years my Mercedes battery still has the stock 750CCA. The CCA doesn't matter if your glow plugs and starter work. It does, but not as much as you think.

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Only diesels in this driveway.
2005 E320 CDI 243k Black/Black
2008 Chevy 3500HD Duramax 340k
2004 Chevy 2500HD Duramax 220k