Need to get some wires through the firewall
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MeefZah
New member
Sit in the driver's seat.
Run an imaginary line through your left thigh (following your femur, basically) and out your knee and follow that imaginary line through the dash and to the firewall. Right about in that spot is a fat grommet with a main wiring loom running through it. The grommet has a ton of room all around to poke another hole and run wiring. There is enough room to actually get a PL-259 connector through there. All my personal installs on 4Rs and Tacos have used this particular grommet and all the ones I've done for others have also used this grommet.
A fast trick on getting wires through the firewall is to take a heavy duty, 18" long or so, zip tie and push it into the slit in that grommet that you made from the inside of the truck. If you are pulling wires in from the engine bay you can poke it 90% of the way through and tape the wires to the end, lube the joint with spit or windex, and then pull the zip tie back in to the cab. If you are going the other way (cab to engine) tape the wires to the end of the zip tie, lube, and then shove it through from the cab side and pull it out from the engine side.
Run an imaginary line through your left thigh (following your femur, basically) and out your knee and follow that imaginary line through the dash and to the firewall. Right about in that spot is a fat grommet with a main wiring loom running through it. The grommet has a ton of room all around to poke another hole and run wiring. There is enough room to actually get a PL-259 connector through there. All my personal installs on 4Rs and Tacos have used this particular grommet and all the ones I've done for others have also used this grommet.
A fast trick on getting wires through the firewall is to take a heavy duty, 18" long or so, zip tie and push it into the slit in that grommet that you made from the inside of the truck. If you are pulling wires in from the engine bay you can poke it 90% of the way through and tape the wires to the end, lube the joint with spit or windex, and then pull the zip tie back in to the cab. If you are going the other way (cab to engine) tape the wires to the end of the zip tie, lube, and then shove it through from the cab side and pull it out from the engine side.
The_Green_Wang
New member
I used a hard straw size plastic tube to get the wires through (think it was a crossbow arrow). Cut it to a smallish size but long enough to see both sides once thru and put the tube over a screwdriver. Jabbed the screwdriver through the firewall (carefully) and slide the screwdriver out while the tube stayed in place. Ran a few wires through and I was set. Removed the plastic tube and was good!
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JSparky
New member
x2. Good video find.
You can also send them straight through where the large factory harness goes through. Nip a small hole in the factory rubber grommet with a razor blade and send a straightened coat hanger through. Tape a lead wire to the end of the coat hanger and use that to feed your other wires through. I've done this on multiple 4Runner's, Tacoma's, and a Lexus GX. Using that smaller grommet is arguably cleaner.
I like to use dynamat or the like to seal off the hole after sending the wires through. Makes a nice weatherproof seal that's perfectly fine for under the hood/firewall applications.
97BlackAckCL
Elite Member
This is what I did on both sides, just cut a slit in the grommet where the factory wires pass through
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Thanks guys, I am trying to do it the cleanest way possible, since it is a 2019 with under around 500 miles on it. I have done the coat hanger through a hole with the xterra but I might do the dual battery setup so the fridge and hamradio and whatever lights that are on the bumper run off of that, I am waiting for the video to be added in the dual battery thread. I guess there aren't that many members in this area or else I would have some guys over.
call me too Asian, but i used a chopstick haha
HurricanePDX
New member
I actually used bamboo skewers! Worked out surprisingly well with the sharp point and how flexible those things are.
Took about 20 minutes to get the wires connected to the battery, and the wires through the wall, also Kenwood doesn't send long enough wires, so they stopped right by the pedals so I have to extend them to under the seat tomorrow.
Yes, it feeds in behind the under mat layer of the driver area. I fed both my amp power wire and the add a fuse lights for the raptor lights through it.
Thank you everyone, I just installed the radio and I have to say it was one of the cleanest wir runs I have ever done. I just have to figure out how to mount the radio under the seat and run the rj45 for the face panel. The mods have begun and I havent even hit 1500 miles on it yet.
Thank you again
Thank you again
Plus 1 on the video find. Thanks for sharing.
Both passenger and driver sides have the rubber grommet you can easily remove, then use a gland to seal up the connection.
On the passenger side pic with the red arrow, you can stretch that nipple out and cut off the end and you will see a sleeve that goes through the factory harness boot and firewall. Just add a little soap or glide and it slides right through.
On the passenger side pic with the red arrow, you can stretch that nipple out and cut off the end and you will see a sleeve that goes through the factory harness boot and firewall. Just add a little soap or glide and it slides right through.
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bring_it_on
New member
How much can you stuff inside the larger driver size grommet? I have a couple of switch wires running there already so not sure how much I can throw in there before I begin making more cuts. I'm pretty sure I won't be able to run two 4 gauge wires through the tiny unused opening above the main grommet. I want to run 2 x 4 gauge wires through there into the trunk. Also, any tips on which way to route the wires in terms of opening up the plastic covering over the wheel well etc? (whether to stary from the trunk and push them through the back or start from the hood and move back..)
Gamma Ray
Banned
Antics Design on ebay sells grommets with holes in them. Here's a direct link.
5th Generation 2014-2019 Toyota 4Runner firewall wire grommet (2 packs) | eBay
In case that doesn't work in the future, here's his profile page. You can see all of his items for sale there.
anticsdesign on eBay
5th Generation 2014-2019 Toyota 4Runner firewall wire grommet (2 packs) | eBay
In case that doesn't work in the future, here's his profile page. You can see all of his items for sale there.
anticsdesign on eBay
97BlackAckCL
Elite Member
Wish I saw this before I tore my hands up routing through the lower grommet last week, my sPod and PowerTray made it pretty difficult to reach through
