Safe to use GOBI rack as ground?

[alexb]

Simple question. Is it safe to use the Gobi roof rack as a ground point for things like LED lights? I did a bit of searching but didn't find a definitive answer.

I found this post here by [MENTION=65614]Antman[/MENTION] http://www.toyota-4runner.org/843765-post4.html

Good news is you only need to run the hot lead into the truck. The ground can be terminated at the rack; Where the ground wires exit at the back of the rack, terminate those with a ring terminal, and place the ring terminal under the bolt head for the rear "GOBI" bracket where it bolts to the roof. I put a stainless star washer between the bolt head and the stainless washer from GOBI to get a solid ground. Tighten the bolt and cover it all with liquid electrical tape, and you are good! Hope this makes sense- I really need to do that writeup...

So I guess that is a pretty definitive answer, but just wanted to double check.

 

[BlackWorksInc]

I mean, it'd be better if you attached it to the bolt going into the roof rather than using the entire rack to flow current; but technically it'd work as long as the part of the rack you're grounding too contacts the bolt going into the body.

 

[Jono.ful]

theoretically, yes, but getting back as close as you can - both physically and electrically - is always best, as the farther away you are, the more resistance you introduce, and the more joints (ie. screws/bolts, welds etc) you have, the more locations there are for failure of the circuit.

 

[alexb]

I mean, it'd be better if you attached it to the bolt going into the roof rather than using the entire rack to flow current; but technically it'd work as long as the part of the rack you're grounding too contacts the bolt going into the body.

theoretically, yes, but getting back as close as you can - both physically and electrically - is always best, as the farther away you are, the more resistance you introduce, and the more joints (ie. screws/bolts, welds etc) you have, the more locations there are for failure of the circuit.

Thanks for the input. It's good to know it's at least do-able. For my 40" LED bar I'll be running the ground back into the engine bay, but for my small 2 rear lights I was thinking it may be easier to ground them with the rack. I'll try to get everything ran back to the engine bay and keep the rack ground as a last resort option.

 

[Moto69Joe]

Thanks for the input. It's good to know it's at least do-able. For my 40" LED bar I'll be running the ground back into the engine bay, but for my small 2 rear lights I was thinking it may be easier to ground them with the rack. I'll try to get everything ran back to the engine bay and keep the rack ground as a last resort option.

For my 40" I have the ground going back to my SPOD. For the rear lights it is grounded to one of the roof bolts.

 

[alexb]

For my 40" I have the ground going back to my SPOD. For the rear lights it is grounded to one of the roof bolts.

Good to know. Thanks :thanks:

 

[BlackWorksInc]

Thanks for the input. It's good to know it's at least do-able. For my 40" LED bar I'll be running the ground back into the engine bay, but for my small 2 rear lights I was thinking it may be easier to ground them with the rack. I'll try to get everything ran back to the engine bay and keep the rack ground as a last resort option.

Actually grounding it through the bolt on the roof for the rack to roof mounting is fine as that goes into the actually body, which is used as a "dirty ground" by the rest of the vehicle. I was just saying that I am not sure I'd want to induce an electric current through the rack itself more than needed. Mostly because even a mild electric current through metal has attractive qualities.

 

[alexb]

Actually grounding it through the bolt on the roof for the rack to roof mounting is fine as that goes into the actually body, which is used as a "dirty ground" by the rest of the vehicle. I was just saying that I am not sure I'd want to induce an electric current through the rack itself more than needed. Mostly because even a mild electric current through metal has attractive qualities.

Ah OK. Makes sense. Thanks for the help

 

[Antman]

Since the rack bolts go directly into the roof and that is part of the chassis it's no different than any of the THOUSANDS of other factory grounds. This isn't a fiberglass boat here we are talking about, the body and frame are grounded.

 

[jicko]

I was just saying that I am not sure I'd want to induce an electric current through the rack itself more than needed. Mostly because even a mild electric current through metal has attractive qualities.

What!??!

"mild electric current through metal has attractive qualities" !?!?!?

:redbrick:

 

[needsmoresalt]

What!??!

"mild electric current through metal has attractive qualities" !?!?!?

:redbrick:

Jicko, Perhaps it is a reference to Maxwells equations on electromagnetism, specifically the "microscopic" variant effects. But this is more likely a comment on Guass's law on flux theorem. But just spitballing.

 

[BlackWorksInc]

What!??!

"mild electric current through metal has attractive qualities" !?!?!?

:redbrick:

Mostly that I've noticed in some cases when current is flowing through an object it tends to attract particulates as well as sometimes cause corrosion to occur a bit faster if given the right circumstances.

Jicko, Perhaps it is a reference to Maxwells equations on electromagnetism, specifically the "microscopic" variant effects. But this is more likely a comment on Guass's law on flux theorem. But just spitballing.

Way too early in the day for me to try and confirm or deny this. lol

 

[2chains]

alexb;what gauge wire are you using? I initially ran 14g from 40 bar back to the rear interior ground point by the jack. Power wires for the front and two rear lights going to the the engine bay via typical windshield method. The wires got warm to the touch after a few minutes for the 40" bar. i ended up grounding the 40" to the rack and things are good now.

 

[alexb]

alexb;what gauge wire are you using? I initially ran 14g from 40 bar back to the rear interior ground point by the jack. Power wires for the front and two rear lights going to the the engine bay via typical windshield method. The wires got warm to the touch after a few minutes for the 40" bar. i ended up grounding the 40" to the rack and things are good now.

The cheap Chinese harness that came with it was 18AWG I believe. I am replacing it with 12AWG for +/- wires. Plan is to run them both back to the engine bay and ground near the battery. For the 2 small lights in the rear I'm using the built-in Gobi wires then the cheap 18AWG harness as they don't draw near as much power and I don't feel any noticable heat in the wiring with them. I currently have them grounded to the rack but I think I'm going to re-route both +/- for them down the passenger side into the engine bay. The 2 12AWG wires will be a tight fit running up the weather stripping on the driver side. Hopefully it all fits.

 

[On Point]

The shorter the wire, the better. I would not worry about running a ground wire from the back of the vehicle to the front. It's unnecessary.