Can I use a different size battery?

MIKECATANA

MEMBER
2008 FORD TAURUS
3.5L
6 CYL
2WD
AUTOMATIC
240,000 MILES

I have the car listed above SEL. It calls for a group 58 or 59 battery. We put a group 26 battery in it as we were in a remote area and that is what they had to sell us. It was smaller size-wise but we secured it properly. Car had destroyed the old battery but it was 4 years old and no longer holding a charge. The CCA on the group 58 was 550CCA. The CCA on the new group 26 was 540CCA. Both 12 volt etc. Aside from the slight difference in size and CCA, is it okay to leave it in the car and not replace it? I was told by (someone trying to tell me I needed a new alternator) that the battery would damage the alternator. How? The voltages are the CCA's are close enough. I know I am missing something. Why is one heavier than the other etc? Anyway, the battery has performed fine. Just wondering if I am missing something. Thank you!

3 Replies

SQM

MECHANIC
6,383 POSTS

Hello,

As long you can secure the battery and the battery has comparable cold cranking amps, it will work just fine. Just remember that when you use a battery which is different size it can sometimes have clearance issue. For example if you were to put a battery that is smaller in length and width but taller, it can make contact to the hood or other components.

So as long there is no fitment issue and as you mentioned the CCA is very close. I would say it will work just fine. Only thing I will mention is that if the temperature is very cold (close to 0 F), might have starting issue due to having a little less cranking amp. But then again you might not experience that issue at all.

Also you do not have to change alternator. The battery size that you put in will not have any issue.

https://www.2carpros.com/articles/how-a-car-battery-works

Hope this answers your questions.
Let me know of any concerns.

Thank you.