I drive a 04 at coupe.....anybody that has upgraded their 5 wire grounding kits, have they seen any improvement in gas mileage, or not so much,

also, should I need to get the 4 gauge or will 8 gauge do,

thanks for the help

Good question. I don't have an answer, but I'd like to know too! BUMP

I seriously don't believe grounding wire (even my 10 wire) has anything to do
with gas mileage. The only thing I can tell you is that it helps if you have a
AT in the way your transmission shifts. The difference is soooooo minute
after a week you don't notice any change. Gas mileage improvement....NOT!
This is one of those mods after a while you ask yourself....was it really worth
the time and $

Gary

so then u reccomend "skipping" over this mod iv read alot about it just didnt see the point...

i would say its not worth it unless you are doing the big 3 upgrade for a sound system. and even then it is much cheaper to buy the wire and cut it yourself but then it comes back to ease vs price

grounding kits make me laugh

I use to think it's crazy,ground wire? but I have an audio system in my car and I do notice the diffrence, also I have a mt..so I guess it all depends on how you want to look at it.but for me it's worth it..

When you are adding larger power draws than stock (ie. larger stereo systems, amp, video) is the only time larger grounding wires are needed.

You have to understand electrical systems to see why the grounding upgrades are needed. They do increase gas mileage among smother shifts and less light dimming / cleaner sound on audio systems.

DC Power flows from negaive to positive.

Yup...

They provide a nice placebo effect for some people but that's about it. I put them on a previous car and initially thought they helped. I took them off about 6 months later and didn't notice anything different. Save your money.