750CCA + 850CCA??

[porteri@email.sc.edu]

Hey guys, I know this is a dumb question and I hate to ask it but being a grad student strapped on cash I wanted some input. One of my 750CCA batteries that came stock in my '08 6.4L just got a bad cell and needs to be replaced, the other checked out fine. I have one good 850CCA (all Motorcrafts) that I took out of my '04 6.0L when I replaced both of the batteries in that truck last year. Is it a bad idea to use a 850 and 750 CCA battery together in my 6.4L? I feel like if there is an issue it would be the 750 battery possibly getting damaged from too much current but I don't see an issue other than this. I would like to get two 850CCA put in this truck but if I can go without spending the extra money until after the holidays that would be even better. Any ideas??

[Turbostang500]

From what i know it shouldnt be a problem if both batteries are good.
It is bad to leave a bat with a dead cell in the system! The good bat will constantly
try to charge the bat with low voltage and that will ruin the good one.

I ran a 800cca optima and a 850cca napa bat in at the same time. Not for a long time but it was fine.

[JSchuricht]

It will shorten the battery life, but for a short time it will be fine. Defiantly better than having a battery with a shorted cell mixed with a good one.

[Antonm]

You'll be fine for a long time. I worked in a junk yard when I was younger and they used whatever they could pull out of the yard for the company trucks. All of them had mismatched batteries, with no issues ever because of it.

[Parts Jimmy]

Will work fine. When one of those fail and you are forced to buy I would buy two Motorcraft 850s.