Where to run Power thru Firewall

[cmcolfax]

Yes, I searched.

2011 SOHC 4.0 5-Speed SuperCab

For those of you who have added amps and / or subs to your truck, where did you pop the power cable thru the firewall?

There is the big cable bundle below the fuse and relay box on the driver side, but I can't see how I am getting thru that. Hell I can barely get my hand on it!

There has to be another spot!

I need to fit true 8ga, nothing bigger.

 

[RobbieD]

Look and see if there's any unused rubber grommets on the firewall. If so, punch a hole through the rubber and run you wire through.

Always fuse an added power wire at its source.

 

[Uncle Gump]

That's where I ran power in and accessory wires back out on my 06.

The big rubber harness grommet lower left side.

 

[Jim Oaks]

I go through that big rubber boot / grommet down above the pedals that the other wires go through. I use this Wire Insertion Tool to poke the hole through and then slide the wire through the opening in the tool.

 

[Curious Hound]

If your truck has an automatic transmission, there should be a nice sized unused grommet where the clutch pedal rod would have penetrated. I jave also added wires through the existing wiring grommet on the passenger side below the heating duct. I have also ordered grommets online and drilled new holes behind the seats.

 

[cmcolfax]

Look and see if there's any unused rubber grommets on the firewall. If so, punch a hole through the rubber and run you wire through.

Always fuse an added power wire at its source.

Always.

I'm mounting a 40amp fused distribution block to the inside of the fender next to the fuse and relay box.

I am picking up the power from one of the two studs that feed that box from the battery.

It will be all of 12" away.

 

[cmcolfax]

If your truck has an automatic transmission, there should be a nice sized unused grommet where the clutch pedal rod would have penetrated. I jave also added wires through the existing wiring grommet on the passenger side below the heating duct. I have also ordered grommets online and drilled new holes behind the seats.

Manual.

I thought about crossing over to the passenger side in the engine compartment and coming thru the firewall over there but I didn't see any good options there either and since I'm coming off the feed to the fuse and relay box to my fuses distribution block then thru the firewall I was trying to keep the run reasonably short.

 

[cmcolfax]

I go through that big rubber boot / grommet down above the pedals that the other wires go through. I use this Wire Insertion Tool to poke the hole through and then slide the wire through the opening in the tool.

That's a pretty slick tool!

I think I have already "spent" $15 worth of frustration trying to find a place/way to get this power wire thru the firewall!

No issues getting thru that thick rubber grommet?

No issues with catching/nicking/cutting wires in the harness when you pushed it thru?

 

[Uncle Gump]

Always.

I'm mounting a 40amp fused distribution block to the inside of the fender next to the fuse and relay box.

I am picking up the power from one of the two studs that feed that box from the battery.

It will be all of 12" away.

I always use a piece of fusible wire in situation like that. The light blue wire coming out of the underhood fuse block is fusible wire.

 

[Jim Oaks]

That's a pretty slick tool!

I think I have already "spent" $15 worth of frustration trying to find a place/way to get this power wire thru the firewall!

No issues getting thru that thick rubber grommet?

No issues with catching/nicking/cutting wires in the harness when you pushed it thru?

That tool is a life saver. I used to poke a hole with a screwdriver and try to force a wire through usually with it just bunching up inside somewhere. Now it's fast and painless.

 

[cmcolfax]

I always use a piece of fusible wire in situation like that. The light blue wire coming out of the underhood fuse block is fusible wire.

View attachment 134751

My fuse block is going right next to the factory box