My Neighbor Is Putting Soap Bars Under His Truck’s Hood-Why?

Sometimes you can’t help but see your neighbors doing odd things. Like the guy across the street putting bars of Irish Spring soap in his engine compartment. You can see it’s Irish Spring brand from the green marbling, and from the smell passing the truck while walking the dogs. What on Earth is that dude doing? Would you believe it is for rats?

Irish Spring soap was the rat solution

Rat Truck
Rat Truck | Getty/MB

Maybe not “for” rats, but because of them. Living in a rural area, you can’t help that there are rodents all over. Cities have them too, but a few rat traps usually clean things up. But in the Boonies, they never go away. It’s just one wave after another. So killing them won’t work.

Deterrence is the only solution. And that is what the neighbor is doing. He swears that since spending $1,500 to replace some of the wiring under the hood of his 2020 Ram truck, he puts new bars of Irish Spring soap near wiring looms. Now, the rodents may come and go but never stay long enough to munch his wiring. 

It’s the smell; rats don’t like the smell. But why are rats wreaking havoc on people’s wiring around the globe? It’s partly due to the wire’s soy-based covering that manufacturers have been using over the last few years. There is some truth to this, but rodents have been chewing car wiring for a hundred years, so it doesn’t explain it away.

Unconventional ways to rid yourself of rodents

Brown rat
The brown rat, Rattus norvegicus, humanity’s worst animal pest, causing enormous damage not only in the consumption of food but to service pipes and cables | Getty

You can use one method of moving your car or truck around so it is not parked for any time in one spot. But that’s a hassle. So people have come up with some unique ways to deal with critters, such as soap bars. There are plenty of other unconventional ways to get pests out of your engine compartment. 

Mercury News recently queried readers about their guerilla tactics toward preventing rats from chewing your wiring. We’ll start with getting cats as one solution that can turn into a problem. Neighbors who suggest this also report that the cats usually go into neighbor’s yards for their bathroom needs. Not good. 

Drier sheets have worked for many as rats don’t like how these smell, either. They’re cheap and available everywhere. Secure them away from exhaust manifolds or other areas where extreme heat could start a fire. Two more products along these lines are peppermint oil, and also Febreze, the spray-on fabric freshener. These are also inexpensive, but does the smell waft into the passenger compartment? If you like how they smell, this would be a win-win.

What about rat devices?

Brown rat
Brown Rat Brown Rat (Rattus Norvegicus) eating through a garden hose | Getty

Some have suggested a rat trap out of New Zealand called Goodnature A24. This little device lures rodents into it, then once inside it bonks them in the head, instantly, and humanely killing the rat. It drops into the trap’s lower tray, and then automatically resets, ready for the next one to come along. No poison, no toxins, simple and convenient. Just remember to empty the bin.

Another device that doesn’t kill, but drives rodents crazy, is the P3 International Under Hood Animal Repellant. For around $20, these little devices make beeping noises that drive not only drive away rats, but squirrels, cats, and other creatures. Supposedly, the beeping is audible to passersby, so it might pose the same negative reaction from neighbors or your kids sleeping with the windows open. But for twenty bucks, it’s worth a try. 

Rat Fink
Rat Fink-the trademark of California custom car builder Ed “Big Daddy” Roth | Getty

Yet, another device that doesn’t kill, nor make a sound, is called Rid-a-Rat. It is basically a small strobe light you zip-tie under your hood. There are also what seems like hundreds of ultrasonic devices that combine both the strobe and soundwave features in one. Prices range from $25 to over $100. 

If none of these work, you might consider building a garage that is sealed off rather well. It will be expensive, but your rat problems will be over. Just don’t store your garbage cans there too. 

RELATED: Eek! Are Tesla Cars Really Attracting Rats and Rodents with Soy-Based Wiring?