Grounding Point

Does anyone know if there is any type of grounding point on roof rack mounting points? I am attempting to hook up a CB Antenna that needs a grounding strap.

Thank you in advance for your answer
Jay

 

Welcome

 

Posting here because I’m also interested in this

 

Welcome. If you're talking stock rack, I would say probably better to run a ground down the truck to something more substantial.

 

I'd say no, there are plastic grommet type things that the roof rack bolts attach to. Might have to fish one under the shark fin antenna and run it to the rear door RH wiring assembly and positap it into the ground wire there. You'll have to drop part of the roof liner in the back though.

 

Won't the coax cable shielding make the grounding connection?

 

Hi

I bolted the grounding strap to one of the bolts of my roof rack. The bolt goes through the roof, so grounding is made on the body, and the frame. That was my reasoning. I'm getting a SWR of 1.5 on channel 1 and 1.2 on channel 40, and 1.3 on 16.

 

welcome

 

But the roof rack brackets those bolts screw into are plastic, and there is rubber stripping running along the entire channel. I fail to see where there is any metal on metal contact. If there was we'd all have rust issues up there.....maybe I'm wrong though.

 

The brackets imbedded in the roof for bolting the roof rack are not plastic, at least not on my 2016. Each bracket is a metal plate with two nuts and metal plate can slide a bit for alignment.

 

aroyalsfan, the bolt screw into a metal bracket, metal on metal, that bracket is in contact with the metal body, which in turn is bolted to the frame.

I could also have remove some paint from the roof rack where the grounding strap is and all the roof rack would have been part of the ground plane for the CB. Since I was satisfied with my SWR, I left as it is.

A photo of the bracket.

 

That bracket is flipped upside down, the plastic is what sticks out of the roof. Personally I would want visual confirmation with the roof liner pulled down that there isn't a foam seal on the metal underside of the roof between the bracket. Perhaps there isn't, but I would want to see it with my own eyes since they go out of the way to prevent metal on metal contact outside the vehicle.

 

yep your absolutely right, that bracket is upside down, there are two plastic sleeves on the other side of that bracket, they fit through the holes on the roof and help to isolate the bolts from the metal of the roof. They nonetheless bolt in metal. Whether the bracket is itself isolated by foam, I do not know, I have not pulled down the headliner to check. I might be assuming that everything has a metal to metal route for the ground plane. What I do know is that I tried it without the grounding strap and had lousy SWR, when the grounding strap was installed, I had descent SWR.

 

Just pick something logical to ground it to and then check the voltage drop across that ground. If the voltage drop is good, your good. If there is a voltage drop, ground it somewhere else and retest.