Battery sizes

[jtvang125]

When my battery went bad back then my brother had one a spare one laying around. It was slightly smaller than the one meant for my car but it gave me about 3 years of use. I just replaced it with a diehard gold yesterday that was the correct size.

Besides the lower cold cranking amps and reserve capacity is there anything else that may cause a problem with using a different size battery?

 

[LTC8K6]

Physical size, no. Unless it doesn't mount securely.

Electrical size, well a smaller size may well have a short life.

 

[Bartman39]

But depending on the car or truck it may require the larger battery/capacity for a reason... If the voltage drops to low during cranking with to little capacity battery then it may crank over but not start...? Also it may do weird things when trying to crank over as well or throw strange codes...?

This does apply to gas engines and for sure diesels... Have seen guys try to get by with 1 good battery in a diesel but end up with all kinds of problems and not know why... Put in 2 good hot fresh batteries and problems go away... With gas engines with a single battery again if its to small in capacity the same problem comes in...