alternator upgrade winch and battery

My batteries are joined a bit different than most, as I use a Toyota Land Cruiser 80 series 12/24 volt switchover solenoid as a turbo controller, giving 24 volts to my winch.

But in your case, yes it is just matter of connecting the batteries in parallel. Positive to positive and negative to negative. Then either one of the negatives to chassis and one to the winch.

Winch negative from chassis is not good enough. Needs to feed directly from battery.

In your case, it's just running a pair of 35-50mm2 cables to the battery in the boot.

Ok great I'll get some cable and do that tomorrow cheers for the help

What winch do you have ?

I'm just running a single red top optima battery on a 95amp suzuki swift alternator and seem to be fine even when winching no power drop or having to rev car

Think it's 95 amp can check if need be

It's a champion c8000ewx