Post by
VStar650CL »
https://forums.nicoclub.com/vstar650cl-u299034.html
Sun Sep 21, 2025 7:55 am
We've found the factory EFB's to be very problematic on T33 Rogues when the customer uses the car infrequently or for lots of short trips. If that's you, you're better off with an AGM. Nissan's choices for the T33 and R53 charging systems frankly puzzle me. They're set up for AGM's, they charge at either 12.6V or less, or 14.5V or more. This is required for AGM battery life, because there's a "death zone" for AGM's around 12.8V which can damage the battery. Yet Nissan eschews AGM's and uses EFB's on the T33, which don't need that. In fact, that sort of charge profile with an EFB causes stratification of the battery when charging is infrequent, and that in turn promotes sulfation. That's exactly what we see in practice -- lots of stratification and sulfation with low mileage or short trip drivers. So I'm with AZ on this, but for a different reason. On T33's, an AGM is actually what the system is best-suited for. Your car will be happier if you correct the factory's mistake.