Hi, I live in a cold weather region where temps drop to -40 deg F or colder during the worst part of the winter, and I don't have a garage. I need to replace the battery in my wife's Suburban which is driven around three times a week. Battery store is recommending a quite pricey AGM battery with high CCA, and also to install a trickle charger. But part of me is still wondering about the cost-benefit part of it and if maybe I should just get one of the less expensive non-AGM batteries with lower CCA. I think I'll install the trickle charger in any case, as I already have a spare one I bought a while back.
AGM batteries
Nov 03, 2025
Last reply: 8 months ago
2 Replies
Perhaps take a combo approach. Battery output goes down with temp, cranking power goes up as temp goes down. I think nameplate ratings on batteries are for zero degrees F. You have to oversize the battery, use thinner oil, and try to keep things warm. At -40F keeping things warm might be worth considering. The trickle charger is a good thing, but at minus forty it won't change things much. Maybe add a block heater?
hth,
bob prohaska
From my motorcycle experience, AGM batteries are absolute winners!
HTH
Chris
Join the Discussion
Have something to add? Share your thoughts — no account required.
Didn't find your answer?
Ask the community — no account required