Forum Discussion
rhagfo
Oct 01, 2012Explorer III
smcrea wrote:rhagfo wrote:
Most Diesels come with two batteries for starting.
It looks like the Chevy gives you the option, and standard is a single of both.
Considering the low price of these two options (a couple of hundred bucks) then I'm wondering if I should just go ahead and get them.
So How does the dual alternator work?
Are they simply ganged together or do they power separate systems on the truck?
The two batteries same question?.. Is the Aux a HOT standby in-case the primary fails or are they simply ganged together in parallel supplying 12v at a higher current for turning? If the second is the case then yes you will get better starter turning but when one goes bad then you can expect the other to go bad at about the same time doubling the replacement cost!!
Well on my Ram CTD they are in parallel, one one each side of the engine bay, both grounded to the frame with a 00 cable between the positive post!
This is one place where maintenance on a diesel can cost more. I just needed to replace my batteries, never one always in pairs.
I got two 72 month OEM batteries at the local dealer for $178 total for both!
The beauty of dual batteries, swap one at a time and you don't loose radio presets!
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