76 AH vs 89 AH so the Group 27 has 13 more AH than 24 or about 20%. Weight
difference is about the same %. About 1/3 to 1/2 of these AH are useable, depending on how you charge them.
Plugged in it don't matter, but for dry camping
you must figure YOUR usage of power and how you are going to charge.. To many variables here to make recommendations.
I have two trojan group 24 in my Bigfoot
TC with 140 watts of solar
and it is just fine, but I am careful. I do some off season (eg need furnace) dry camping
and watch DVD's n the evening, so do use a bit of power.
Remember one thing. If you go to small and run the battery down, then you will be replacing it much sooner.. And if you really want to manage things you need a good monitor or volt meter to keep tabs on things.
AND I have never ever seen a battery in an RV go 11 years for nobody nohow. The environment is to unpredictable with humidity, temperature swings, uneven discharge and charge rates etc. it just don't happen. Just saying. ESPECIALLY with solar
panels which do a charge/discharge cycle every day they are hooked up.
IMHO, of course.
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