I want to ground 0gauge to frame on my quad cab ram.. I dont want to ground to underseat bolts or any area from the inside of cab. The shortest length from mount to frame rail is 1.5 ft to inside cab.  My idea was to have a bolt weldeld to frame closest to my wire entry to cab. Is 3or 4ft ok for a ground wire at zero gauge.. 

Don't weld to the frame

What bout a long bolt going throught the frame..paint removed on both sides of contact points of the bolt using washers to help touch the missing paint spots 

That's the way I do it.

how long of a 0 gauge can i use before it becomes useless to use such a thick gauge for ground, is 3.5ft from frame to inner cab ok,

in the fosgate manuals they say never to have a ground longer than 30"

Edited April 24, 201312 yr by 1two3

^^ Meaningless for them to tell you that, especially not knowing your wire gauge.  This type of advice is geared twards keeping a moron from running a 20' ground with 10 awg wire for a 3Kw amp...

 

Your ground can be as long as you want.  As with (+) run of your cable, it all adds up total restance.  So a 4' ground and a 16' (+) is no different than a 1' ground and a 19' (+).

thanks for the help guys the last answer was what i was hoping for... im not planing on running two 0 gauges to batery for pos and neg,, just a 3ft ground to a 12ft positive