[AtlWtr]

I bought a used Tahoe Q3 with a 3.0L, and the cranking battery has died. I have a deep cycle battery for the trolling motor. Not sure where the other electronics are hooked up. Is there a battery that is recommended? I see there is a wide spectrum to choose from. Thanks

[AtlWtr]

Let me try asking another way. Since I need a cranking battery should I just look on consumer reports and buy the best car battery?

The old one was an Interstate RV/Marine cranking battery. Any thoughts on this battery?

[HighTrim]

Get the biggest CCA battery that you can fit,well worth the money

[bruceb58]

I would still buy a deep cycle battery for your cranking battery. I get mine from Costco. I use a deep cycle battery to crank over a 7.4L engine. It will be fine for your 3.0.

[DRIFTER_016]

Deep Cycle and Starting batteries are designed differently for different purposes. Buy a marine cranking battery for starting your engine.
A deep cycle battery is designed to be deeply discharged repetedly by slowly draining by a lower amperage draw like your boating electronics, trolling motor etc.
A starting battery is designed to quickly supply high amperage to start your engine. The draw is short in duration but intense.
Currently the best marine batteries are made by Optima. IMO
Buy the battery with the highest Marine Cranking Amps (MCA) that will fit in your mounting bracket.

[bruceb58]

Originally Posted by DRIFTER_016

Deep Cycle and Starting batteries are designed differently for different purposes. Buy a marine cranking battery for starting your engine.
A deep cycle battery is designed to be deeply discharged repetedly by slowly draining by a lower amperage draw like your boating electronics, trolling motor etc.
A starting battery is designed to quickly supply high amperage to start your engine. The draw is short in duration but intense.
Currently the best marine batteries are made by Optima. IMO
Buy the battery with the highest Marine Cranking Amps (MCA) that will fit in your mounting bracket.

A deep cycle battery is designed with thicker plates. Because of that, it can tolerate deeper discharges but puts out less peak current than a starting battery that is built with thinner plates that have more surface area. Will the starting battery deliver more current to start your engine...yes. Will the deep cycle battery be able to supply enough current to start your engine...also yes. As with any battery, deep cycle included, the less you discharge the battery before it is recharged, the longer it will last.

The Optima is a good battery but way overpriced for what it delivers.

[Boatist]

I agree with Bruse that a deep cycle will usually work fine as a starting battery unless you have a very large engine that is hard to crank. Yes the plates are thicker so you can not put in as many plates in the same size battery so slightly less current.

However I would buy a regular auto cranking battery unless your mounting it up front in the boat where they take a lot of pounding, then I would go marine.
The reason I like a auto cranking battery better is.
1: Much cheaper, go to Costco, Walmart, Sams club.
2: Auto cranking battery has a 3 year free replacement and 100 month pro rated warranty. Marine battery is 1 year free or less and 36 month or less pro rated warranty.
3: I like my boat cranking battery to be the same size and type as my tow vehicle battery, so batteries can be easily changed between boat and Truck. If anything needs to be changed I change the cables in the boat to be compatable with the truck. Never know when someone might decide they need your truck battery more than you.

As far as brand I buy what ever has the best deal. You can spend 3 times as much and the battery will last no longer.
What determins how long the battery last is not the brand it is how you care for your battery. Deep discharge it and let it sit before recharging and you will be lucky if it last a year.

Starting batteries should not be discharged below 80 percent of full charge and Deep cycles should not be discharged below 50 percent. The longer either is discharged before recharging the more damage is done. Also in hot summer month must recharge at least one time a month and winter every 2 to 3 month. Check the water level once a year and add distilled if necessary but also charge after.

I have not had a battery that did not last at least 6 years in my 1980 boat and My deep cycle is so old that I bought it back when price club still sold Delco Voyager Batteries

[dingbat]

I run a bunch of electronics and like having redundancy in powering them if need be. A starting battery will start the boat but will not run the electronics for long so I opted for a pair of deep cycle batteries. I run grp. 27 AC Delco Voyager Batteries and get very good life from therm.

I replaced one the end of last season after 7 years of service after I left the washdown pump on over the weekend which killed it. The second one is still has plenty of life left in it.

[tashasdaddy]

i have had great service for my interstate rv/marine starting battery. it has out lasted another battery i have. definately not trojan, i have had 3 fail in less than a year. i bought one, trojan just keeps replacing it. Dead Cells. it's a pita, to have to take it back.