05 F350 ex cab. Amps are going to be on a rack up against the back wall. Should i ground the amps to the rear wall which would be like a 10" run or to the bottom of the "shelf" which would about a 16" run. The grounding wire will be 4 guage also. It seems the heavier guage metal on the shelf would be better but i figured i'd ask to make positive. Thanks

 

I suppose a lot of people ground their amps right to the chassis. Depending how big/many amps you are running, that might be the best solution.

My own amp (just a Pioneer GM-5000T) is mounted under the driver seat and grounded to the seat mount. Probably not smart but it's been working for over a year without any difficulty.

 

i dont think i've ever seen anyone ground them directly to the chasis unless its a serious competition system. I was told to keep the ground as short as possible to avoid noise. Grounding it to my chassis would need like 6-7 ft of wire.

 

Yes, the shorter the ground the better. Like I said, my amp is mounted under the seat and grounded to the side of the seat... it's like 8" away. My Capacitor is also grounded there, which is maybe a two foot run.

Pic:


You can see the grount to the seat there pretty well (look for the green tape at the end of the wire)

I still have to shorten those wires up and hide them, but it works very well right now

I guess just find the closes piece of solid metal to the amp. The back wall itself might be a good choice.

 

You'll be fine grounding on the back wall. Make sure you sand off the paint to get a good connection. I did this and my amps work great. My 9.0 has a longer neg run then I would perfer only because it was added after my Viper and I used the same grounding spot. I just didn't feel like tearing my truck apart or ripping the damplifier off the wall to find another spot closer.

That back wall ties into the chasis decent enough.

 

after reading the guys post above and below me, i think i'm just going to ground it to the bottom shelf. He grounded it to the back wall and it dosnt seem like its grounding enough.