Okay, I've got my winch in place. I'd like to add a second battery and I'd like advice on this. Thinking of going with Optima. I assume yellow top but some guy at a parts store said red top would be better. And what's the best system for having the two batteries "talk" to each other ... or should I bypass that? Everyone I talk to has an opinion, but I'd rather query the membership here since some of you guys are real off roaders!

 

If you are looking for a dedicated aux. battery, a yellow top is a great choice.
It also doubles as a cranking battery, but can be used for a winch with its deep-cell technology. There are more than a few good companies that will set you up with an isolator for the two batteries. The company that I have experience with is Painless Performance.
Excellent products and customer service-you'll spend a bit more for the quality.
(By the way, I run one yellow top for my rig-it doubles as a cranking and aux. and I've never had issues.)

 

it's called a "battery isolator" - takes alternator input, charges start battery first, then secondary, uses secondary battery for auxillary devices, will not drain your start battery.

for winching, you want high capacity and high crank amps. also if you have an electric compressor etc.
if you're going to be running a fridge, stereo, CB radio, lights or anything else for longer camping type trips, you'll lean more toward a deep-cycle type battery.