Road salt.....myth or fact?

[rdcl]

Having your vehicle covered with road salt is a fact of life in N.E. Ohio during the winter months. I wash it when there is a break in the weather then the next day it is covered again. Oh well.

I've often heard folks say that the corrosive aspects of road salt remain inert when the temp is AT or below freezing.......and the stuff does not become corrosively active until the temp is ABOVE freezing.

......in other words....you are more likely to promote rust by pulling a salt-saturated vehicle into a heated garage.

Which do you believe?

( I know, I know.....a car is just a "tool" and we should not worry about such things.....but they are rather expensive tools are they not?)


Russ

 

[venomballistics]

I'd give the theory some credence. Its a chemical reaction. As such the reaction is accelerated by heat.
the fly in the ointment is that the salt shifts the freezing point down the scale. 32 degrees is no longer the point where things freeze.

one thing I thought about was using the nearly spooky Ultra Ever dry coating on the underbody of my cars to just keep this problem out of the equation.
Ultra Ever Dry - YouTube

It seems Rustoleum or Krylon licensed the stuff so we have easier consumer level access to the stuff.
Its worth a shot.

 

[NYlakesider]

Having your vehicle covered with road salt is a fact of life in N.E. Ohio during the winter months. I wash it when there is a break in the weather then the next day it is covered again. Oh well.

I've often heard folks say that the corrosive aspects of road salt remain inert when the temp is AT or below freezing.......and the stuff does not become corrosively active until the temp is ABOVE freezing.

......in other words....you are more likely to promote rust by pulling a salt-saturated vehicle into a heated garage.

Which do you believe?

( I know, I know.....a car is just a "tool" and we should not worry about such things.....but they are rather expensive tools are they not?)


Russ

We sure get our share of salt up here

I swear our road crews think salting is a Olympic event and they want the gold prize!

The common talk is to leave the old salt on as its there and has done its damage IF A VECHICLE IS LEFT OUT SIDE. Wash it off and then add new salt and its back up to full potency. A heated garage is the worst as everything melts off and as soon as you go out you get new fresh stuff.


My Corvette sits in a heated garage under a dust cover for 6 months a year for a good reason.

 

[Knigge]

Thats right, salt becomes inert below a certain temperature, imagine all the salt under your car eating thru the steel a wet summer day, did you know thar sugar has the same effect on ice as the salt ? but sugar is more expensive so they use the darn salt in stead.

 

[venomballistics]

Thats right, salt becomes inert below a certain temperature, imagine all the salt under your car eating thru the steel a wet summer day, did you know thar sugar has the same effect on ice as the salt ? but sugar is more expensive so they use the darn salt in stead.

that may or may not be true ... but assuming it is, I get this visual of sugar coated cars swarmed with fire ants.

rust or colonies of ants crawling out of the vents on a Sunday drive ..... I might take the rust here

 

[gregintenn]

It is my understanding that the corrosive effect of salt, like black powder residue, is due to the fact that it attracts and retains moisture. Usually, cold air is dry, and in cold weather, the moisture present is frozen. I imagine it wouldn't attract frozen moisture the way it would attract moisture on a warm humid day.

I am not a scientist, nor have I done any studies on this. It is simply my opinion, and worth about what you paid for it.

 

[GaryS]

This sounds right to me. Like you, I'm not a scientist, but it intuitively makes sense.

It is my understanding that the corrosive effect of salt, like black powder residue, is due to the fact that it attracts and retains moisture. Usually, cold air is dry, and in cold weather, the moisture present is frozen. I imagine it wouldn't attract frozen moisture the way it would attract moisture on a warm humid day.

I am not a scientist, nor have I done any studies on this. It is simply my opinion, and worth about what you paid for it.

 

[Rastoff]

Thats right, salt becomes inert below a certain temperature, imagine all the salt under your car eating thru the steel a wet summer day,...

Well, salt by itself is nothing. It takes the combination of salt and water to start the corrosive effects.

So, yes, keeping the car below freezing will help. It's not the whole answer though. It's also impossible to remove all the salt. There are just too many nooks and crannies that hold on to the stuff.

There are some great undercoatings. It's worth the few hundred dollars to get it done if you care about your vehicle.

 

[max]

Never thought about it, just wash my car very often.

 

[sipowicz]

A safe bet would be to move someplace where the temperature never goes above freezing.

 

[Mcwsky09]

Humidity is definitely a factor, I heard of a truck that was used in the salt mines for years and years, not a spot of rust on it until it was brought to the surface and then it rusted away completely very quickly.

 

[Ben_hutcherson]

did you know thar sugar has the same effect on ice as the salt ? but sugar is more expensive so they use the darn salt in stead.

Not quite true, salt is actually more effective as an ice melter for a given amount applied. This is due both to the lower molecular weight of sodium chloride and the fact that when it dissolves it dissociates into sodium ions and chloride ions(sugar does not dissociate). Along these same lines, calcium chloride, which dissociates into one calcium and two chlorides, is actually an even more effective ice melter but is more expensive.

Look up "freezing point depression" for a more in-depth discussion on this.

 

[4barrel]

We get northern cars at the auctions here in the south. If you are going to drive them for a while you don't wont them because of the rust. People are still driving 60s & 70s around here with no rust. I have an 81 Chevy short wide 4x4 in good shape with no rust.

 

[CAJUNLAWYER]

That's why we don't use salt on our roads down here. If we do get the occasional icing problem we use Tony's

 

[Faulkner]

You northern folk may laugh at us and our driving skills when we get a sprinkling of snow and ice . . . but our cars don't rust. I can live with that.

 

[rwsmith]

This is similar

This is similar to the situation we had with a local mill that put out sulfur compounds in a powder that would settle on cars (and everything else). People would wash it off with a hose not realizing that unless they cleared the powder completely off the vehicle, the water would just activate the compounds that weren't corrosive when dry.

 

[MO_mule]

rdcl:

The corrosion reaction is temperature sensitive. The rule-of-thumb (by a fellow named Arrhenius) is that a reaction rate doubles for every 10 C (18 F) rise in temperature. So, there is some truth to the argument that a salt-laden car will corrode more quickly in a warm garage. However, car manufacturers take some pains to coat the car with protective coatings before the paint is applied. This slows the corrosion of the metal since the coatings have to be breached so that the salts (ions) can get to fresh metal.

Wash the salt off when you can. It's never the same dirt twice! Spray the wheel wells thoroughly and the underside of the car. We car nuts can't achieve washing perfection in the cold months but every little bit helps to keep the vehicle in good shape.

Chris

 

[Arik]

I don't wash my car till July. By that time the rain has helped. My cars never rusted

Sent from my SCH-I545 using Tapatalk

 

[ruger-p94]

Having lived up in Canada for a while I know a lot about road salt. I would wash my truck just before winter and again in the spring when all the snow and cold is gone. Never wash your truck or car in a car wash in the winter. A lot of them recycle their water and you end up blowing salty water under high pressure into every nook and cranny.

 

[finesse_r]

It is a fact. Road salt is bad for your gun.