Hey everyone,
I need to run some 4awg through the firewall on a '99 Explorer Sport. Any pre-existing locations that the 4gauge will fit through? There is a pretty big grommet behind the brake pedal that a thin cable is running through (parking brake?) and I was thinking of using an exacto knife and making the middle bigger.

Any other suggestions?

Also, where can I ground a 4awg in the cargo area?

Thanks

thats exactly what i did, i just used the grommet behind the brake pedal, i made my own hole and sealed it up once the wire was through it. works fine for me.

Find a convenient access hole to run a separate ground out of the cargo area, to the frame. Then make one ground from your component to the frame, or one from the frame to a central location for multiple components. I assume that if you need a 4AWG power wire, that you need more than a ground to chassis. The chassis grounding wires are not very large. Good luck,
Don

I ran my wire through the same grommet, just cut it open a little more. As for grounding, I ran the wire under the back seat and bolted the wire down with a bolt that was already bolting something down (I think it was a seat belt bracket). Hope this helps.

I repeat, the chassis is grounded to the frame with very small gauge wires. I just removed my 99 body from the frame. I know what those wires look like.

If you actually need 4AWG wiring, then using chassis grounding would be relying on existing ground wires of the harness. Those wires may not be sufficient for the kind of amperage which a 4AWG wire can pass.

If you are only adding a small load of say 10-15 amps, then ground it to the chassis. But 4AWG wire suggests much more current than that. Add a better ground, either to the frame, or all the way to the main ground wire. Good luck,
Don

I repeat, the chassis is grounded to the frame with very small gauge wires. I just removed my 99 body from the frame. I know what those wires look like.

what about the bolts?

what about the bolts?

I assume that you refer to the ten body bolts being grounds? If so, then no, they are not an electrical connection between the body and the frame. The rubber doughnuts isolate the body from the frame.

Look at the ground wires behind the two kickpanels. Basically all of the electricity travels through those few wires. They are fine for the factory accessories. But they are not adequate for another 1000 watts, from say an amplifier.
Don

Yeah those, I wondered if they were rubber isolated or not, I figured they'd be fine fo the average joe. I know of the grounds you speak of... not much at all. The little strap under the hood as well, at the rear. I added extra ground wires myself as well.

I have two 4 ga positive runs to the back into two 1 farad caps that ground to seperate bolts that used to hold the cargo hooks in the back down. My 4 amps have 8 ga wires each out of the distro block. Negative wires to into a distro block that has 2 ga going to a cargo hook bolt on the other side. Also have 2 ga from the grounding bolt directly in front of the battery to the battery neg and 4 ga from the battery neg to a bolt on the alternator. That and 4 ga from the alternator output to the bat. Battery gauge only moves at idle and I've only got the 90 amp alt..........

Good work. A 4AWG wire has the potential to pass more electricity than the stock system has room to absorb. Most smaller amps take no more than 10 gauge wire, and the body can handle that extra power.

Very high powered added loads need to have two added paths, for power and ground.
Extra ground wires are always a good idea.
Don