The parts book says my truck takes a 650 CCA battery, but I saw a 885 CCA battery beside it for the same price. The parts guy said unless I have a larger alternator, the bigger battery won't get fully charged, and actually not be as good as the 665 one, and the warranty could be void.

Anyone here heard of this?

 

New to me.

 

Parts guy don't know what he is talking about

 

CCA is a measure of the "burst" energy a battery can deliver.

It is done by making the plates more spongy.

Price is --- the battery does not last as long, all things considered.

Your choice.

If the 2 batteries have the identical amount of lead (weigh it dry), the higher CCA version will peter out sooner.

 

I've replaced many battery's with larger CCA ones and never heard that before and never had a problem with one. Did a google search and here are a couple of quick reads, didn't find anything on the charging thing the desk jockey was talking about but learned about the reserve capacity never paid attention to it or knew about it. Learned something new today already and only on the 2nd cup of coffee.

Battery Tutorial

Battery Basics - Selecting a Battery

 

Technical note.

A higher CCA battery, having more exposed surface area, do require more current to charge IF it was in fact drained more.

However, if the start (glow plugs, cranking, etc.) required the Identical amount of energy(watt-seconds), measured by voltage X current X time, then there is no difference in the amount of time required for the identical alternator to put energy back into it.

Other cases:

Possible Case A:

Higher CCA battery means the vehicle start easier / faster because the diesel is spun at a higher RPM.

That means less absolute amount of energy is drawn, and with it, less recharging time vs. a lower CCA battery that is identical in weight.


The point is --- without knowing specifics of each start, the conclusion cannot be made that a higher CCA battery takes longer to charge and might hurt the alternator.


If you have 2 batteries with the identical mass of lead (the reagent).

Spongy lead --- mean more burst power.

But weaker plates (break sooner, and when they break, you lose that whole surface area).

Thick lead (plates last longer) That is what deep cycle batteries do.


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If I live in Northern Ontario (cold) I choose the higher CCA.

In Southern Ontario, lower CCA.

 

THX for the replies.

I'll do some reading on the links this aft. scraprat.

I've always gone for the higher CCA batteries, but if what you said gearloose, about the higher CCA battery, maybe that's the reason for the better warranty on the 650 CCA battery.

 

My dads 03' SD came with a 750 CCA from the factory my 04' came with a 650 CCA battery. Both are V10s so I suspect Ford used the battery they had handy. My dad replaced his battery a little while ago with a Duralast Gold top (65-DLG)with 850CCA and 1000 at 32 degrees 150 reserve, no issues. Parts guy is full of it. The indicator on my OE battery is starting to dim, I think I'm going to need a Gold top soon.