do the big 3, yes it will help. it sounds like you may have a bad ground somewhere in the factory system already. the big problem with caps, is that they mask any problem. i have seen a 16farad cap hold the lights from noticeably dimming with more than 100a of draw beyond what the factory system can support at max. if you take a meter, you will see that ot is all an illusion, and the voltage is still dropping, it just does it softly, so you can't see it. on top of that, it extends the draw on the alternator and wiring during recovery. in short, it tricks you into cooking your own system. on a side note- it has been mentioned what they are good for. i have a 2farad on my home-built 14v 20a bench power supply, and it, allong with a choke, keeps clean enough power to use on newer amps and heads without damage. what brand is that 5 farad? i might be interested in snagging it for my next 150a bench supply project. by the way, your battery should be good enough to keep your power perfectly clean, as they have been doing for ages..... i just don't want a battery used indoors anymore..