wire routing

[racerman1cars]

Hi, I just got a 2006 Chev ext cab z-71 and was wondering where the best place on the firewall to drill and gromet a hole? I had a 2005 and it had a flat place on the fire wall beside the steering colum, but this truck does not seem to have the same area.
Thanks
Steve

[Jim202]

Hi, I just got a 2006 Chev ext cab z-71 and was wondering where the best place on the firewall to drill and gromet a hole? I had a 2005 and it had a flat place on the fire wall beside the steering colum, but this truck does not seem to have the same area.
Thanks
Steve

Why does everyone always want to try to install a new grommet through the firewall? You install a grommet and you have to seal it up with RTV or some other form of sealant to keep the water out. That is a pain in the rear.

In all the years I have been installing two way radios, I was always able to add a hole through the existing rubber around the emergency brake cable or beside the steering column or in the grommet where all the wire run. Take a flashlight and look under the hood in front of the driver side. Look down to where the cables and such go through the firewall. You should be able to locate enough space to poke a hole through one of the rubber pieces there. Then go on the inside, pull down the floor mat and see if you can find the same rubber grommet. Use of a drill will allow you to make a new hole. Just be careful you don't damage any of the wires where your working. If it is one of the older vehicles, it has a real thin membrain and you can poke a hole with a Philips screwdriver.

Make sure the hole is smaller that the wire. That way it will self seal when you poke it through. If you make it too small, it may not go. A little silicon grease will allow the wire to slip through with ease. Have been able to run the high current wire in this fashion for 100 watt radios all the time. Even run the speaker wires for the siren units.

Jim

[FireCpt809]

On the other hand My shop never uses factory grommets unless they are designed for the purpose of adding extra wires such as the new Chargers and select vehicles. We always drill a sutible size hole in the firewall and use a rubber grommet then run the wires and cables then seal it with silicone. We have found that poking holes in existing wiring harness boots and grommets is very risky and can nick or cut a factory wire and lead to expensive repairs.

[Andy Corbin]

One of the things I have done was to drill a 3/4" hole through the firewall and plug it with a rubber NMO antenna hole plug. Before installing the rubber plug, I would take an exacto knife or razor blade and cut an "X" in the middle. The wire(s) poke easily through the center and self seal around the wire. When it comes time to uninstall, simply leave the NMO plug in place and the hole will self heal and keep water out.

Andy

[racerman1cars]

Hi, I am looking for a place on the fire wall to drill a hole and run a piece of # 8 from the red box under the hood to the inside of vehicle. vehicle is a 2006 Chevt Silverado ext cab.

[HLA]

i'm with Jim202, I use what's already there from the factory, if you use the correct plastic tool to poke and feed the wires then you don't cut anything. I think you have a better chance of cutting something by drilling a hole. the factory grommets and seals have more than enuf room for a #8 wire

[racerman1cars]

Hi, You and Jim are right on, I used the factory grommet and went in above the wiring. worked like a champ.
Thanks
Steve

[SlimBob]

Nice idea on the NMO hole plug....

[FireCpt809]

i'm with Jim202, I use what's already there from the factory, if you use the correct plastic tool to poke and feed the wires then you don't cut anything. I think you have a better chance of cutting something by drilling a hole. the factory grommets and seals have more than enuf room for a #8 wire

The "Correct" tool is nothing more than a sharpend piece of tubing. Ive seen more damage done by those than actually getting under the dash checking the other side of the firewall. Drilling a small pilot hole then drilling the approprate size hole and using a rubber grommet. When I do it its to run mutiple wires, strobe cables and what not. I need someting bigger than a single 8g. The Ford,GM and Chrysler upfitter guides actually recommend this rather than poking holes in grommets.

[techtonics]

I usually look for where the factory would have put the feed through for the clutch booster which has a punch spot for a drill bit to use.