Batteries??

Wet cell LA batteries are destroyed by corrugations within 2-3 years in the OKA. They fall apart internally.
Since changing to AGMs, I have had 9 years for the first and 5 and counting for the second.
They are attached to the chassis, not under the "bonnet". I have no idea if the reported heat issues with AGMs under the bonnet are true, or just another urban myth.
Our new build OKA will have a Li crank battery @ 8kg +/-.
Cheers,
Peter
OKA196 motorhome

Hello, I’ve always used Century/Yuasa batteries 4wd or boat batteries in wet cell are good engine starting batteries.
Last time I bought a duel purpose AGM that has both the normal battery posts and a threaded bolt to connect lower current items. Theses batteries are rated for starter motor currents and have a good warranty.

Every battery under the bonnet will suffer from heat, it’s best to put it in an insulated box and if possible run a fresh air duct to it.
I bought 2 one for the 4wd start battery and one in the back to run the a fridge off.
The fridge battery is charged by a 12/12v charger for optimal charging.
After about 12 months the one in the back wasn’t holding its charge properly, sometimes down to 12.4 volts after 3 or 4 days sitting, Battery World tested and replaced it and haven’t had a problem since 5 years total.

It’s also good to regularly charge your Start battery with good quality 5 or 7 stage charger, and use the recondition cycle as per its instructions, alternates don’t charge batteries optimally, specially the smart ones.

John, retired motor mechanic

We've had an Optima Red in the DMax since 2018. Doesn't have a hard life, but still seems strong.
Also recently put a big Century C12-120XDA in the camper ....... will see how that goes.
Batteries seem to be one of life's bugbears .......... always needing charging, replacing , causing worry.

Cheers
Jim

Thanks everyone for the replies.

Yes, corrugations killed those two batteries.

I have Optima at the top of my purchase list, just wanted to hear what others had to say.

The crank battery location has a small snorkel that 'scoops' air from inside the wheel well onto the battery, it's not much, but it's something, I could enhance this if I wanted to I guess.

The price of 1 Optima is about the price of 2 average deep cycle / crank batteries. Everything's a gamble.

What about Century batteries? They were always considered bullet proof, then not, then they were again.

Optima's on the other hand, I've only ever heard that they are the bees knees.

Some years ago i took advice from here and tried a supercharge gold series 800cca n70zz, it went over the simo, gibson, did Binns track, and was still going strong when i went lithium and passed it on. They are on the cheap side of n70zz offerings, about 180 on special at frankies etc
Lithium is dcs 260 underbonnet if you want to google them,

FWIW we have owned our Patrol since 2011 & are now on our 3rd replacement crank battery. All wet cell lead acid.. Each as been the same Repco branded one & each has lasted around 4 years. It is worth noting however the last one had seen a significant amount of corrugations travelling from Vic to Broome via Oodnadatta, & Old Andado to Alice, across the Gary Junction Rd to Telfer, down to Karlamilyi, & across to Newman, & then to Mt Augustus & Kennedy Ranges & an excursion into the east Pilbara. Up & down the Cape Leveque Road multiple times (before it was sealed) & then from Broome to Cairns via Kalumburu & Walcott inlet, the Gregory NP (& Buntine Hwy) & the Limmen NP & then to the tip of Cape York via the Old Coach Rd & the OTT.

So I think it fair to say the last battery had seen more corrugations than many, but it lasted just as long as the previous one. I reckon 4 years is about average for every crank battery I've ever bought across a range of vehicles over the years, & the fact that the Repco ones have given that even in what have been quite extreme conditions of corrugations, heat & humidity says a fair bit in the favour of of them. I won't hesitate to buy another when the time comes ...... & although it hasn't been needed I like that there are Repco shops & agents right across the country who will honour the battery's warranty if required. Eg. Last replacement battery was purchased (in September '21) from a Repco agent in Weipa.

I did have a pair of Yellowtop Optima's crank batteries in our bus which were still ok 4 years after I bought them when I sold the bus. They probably got more than my average of 4 years for crank batteries but were not in an engine compartment.

Our deep cycle Ritars in the Patrol have been replaced once. First set lasted 9 years & 10 months, but they are not in the engine compartment.