Wiring harness pass-throughs

Where to find it. Firewall grommets, floor-pan penetrations and any point where a wiring bundle passes through sheet metal or a camper subfloor.

Application photo Coming soon

Walkthrough video Coming soon

How it works & how to apply it

This is the entry route that costs owners the most money. Rodents chew the soft rubber grommet, follow the loom into the dash or living space, and take the wiring insulation with them. Seal the grommet and the first few inches of loom and you have closed the most attractive door on the vehicle.

1·2·3 How to apply it

Trace the main harness from the engine bay through the firewall, then along the underside of the floor.
Wipe the grommet and the first 12 inches of loom with a dry rag so the surface is free of mud and road salt.
Brush a heavy quarter-inch collar of gel all the way around the grommet where it meets the metal, with no gap.
Carry the coating six inches along the loom in every direction leading away from the hole.

✓ Things to consider

Work on a cool, dry vehicle. The gel grips best on a dry surface and will not sag once it sets.
A two-inch chip brush lets you reach behind the loom without pulling on connectors.
Most harnesses pass through a grommet at each end. Check both sides of the firewall and the floor.
Take a photo of each treated point before you park for the season so next year you know where to touch up.

✕ Things to avoid

Do not pack gel into electrical connectors, fuse boxes or relay sockets.
Keep it off the exhaust manifold, turbocharger and downpipe, or anywhere that runs above 400°F.
Do not unclip, stretch or reroute a harness to reach behind it. Coat what you can reach safely.
Do not thin the gel. It is meant to sit thick; thinning it defeats the barrier.