Wednesday, Sep 07, 2011 at 07:12
Like Captain, Cseajay and others, I did exactly as you describe 3 1/2 years ago and it works fine, even in the snow!
Toyota sent out a bulletin about 3 years ago specifically recommending what you described and NOT putting a 3rd battery as per ARB and Pirhana. Putting in a 3rd battery moves a lot of OE wiring and fuel lines, and Toyota claim it could void the warranty. They move some scary stuff at the rear of the passengers side under the hood inc the ABS system.
The reason that splitting the batteries is not reccomended, and where the story came from is that ARB and and Pirhana miss out on selling you about $700 of battery tray, and installation given that everything is already there. So it MUST be no good.
Also I advise using a Surepower ( ARB) or Redarc 200A isolator and wiring it so it can be overridden ( like a jumper lead), and you can boost the alternator voltage by 0.6V by putting a diode instead of the fuse in the Alt-s fuse location in the fuse box under the bonnet. Usefull for charging ifyou have a camper.
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