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By September 1, 2022No Comments


Think about it, Canada is perhaps the harshest environment in the developed world for automobiles. Freezing winters, humid summers, poor roads and a propensity to rely on corrosive de-icing chemicals severely shortens the life span of the average new car.

Whether or not to rust proof your car is a sure fire means of inciting a debate in the automotive community. It is surprising that there are still industry “experts” that decry all rust proofing as a waste of money as cars are better made and protected. Their most laughable advice, that merely washing your car underneath each spring will prevent rust.

If you are lucky enough to winter all season in Florida (inland) or trade your vehicles every three years you can skip to the next page, though the next owner of your car will wish you finished this article.

In Ontario, Quebec and the Maritimes, highway departments heavily use calcium chloride and magnesium chloride. The brine sticks to metal when wet and when dry become a powder that permeates every nook and cranny of your car. Even dry both chlorides attract moisture starting the rust cycle all over again. Merely washing you car will not remove the brine residue and the best precautions taken by the factory will not prevent your cars from rusting.

•    What “High Salt” Diet Is Costing You:

A view of traffic conditions in Downtown Toronto

Leaving aside the environmental and infrastructure damage done by road salt, the cost to the automotive consumer is immense. On average a new car in Canada is $30,000 financed over some 62 months, according to J.D. Power and Associates. The financing period has been growing steadily as consumers seek to keep car payments affordable in a recession bound economy.

By the time a typical new car owner has paid off their ride it is ti

me for a replacement, a DesRosiers study indicated that close to eighty percent of untreated vehicles showed some signs of rust at the six to seven year mark.

Regular rust proofing can extend the integrity of vehicles body well beyond the average new car ownership period, which according to global market intelligence firm R.L. Polk, has reached a record six years.

A rust proofed vehicle combined with the improved and drive train durability of modern cars means that the vehicles life span will exceed the 13-year mark. In effect doubling the useful life of a new car and saving the consumer over $30,000.

•    Do It Annually:

The most popular form of rust proofing in Canada is a light oil based material that is sprayed on annually to protect your car. The oils contain a rust inhibitor, lubricant and a capillary agent that allows the rust proofing to creep into all areas of the bodywork, coat the sheet metal and expel moisture. Rust Check and Krown are the industry leaders with each company having their own proprietary formulas.

New entrants to the marketplace include Corrosion Free and Canadian Tire, which uses the Corrosion Free product. Rust Check also offers a heavier weight oil spray that is designed for underbody application and will not be wash off even after a couple seasons of salt spray.

The Canadian Automobile Association (CAA) and the Automobile Protection Association (APA) recommend the oil spray method and advise against wax based and electronic alternatives. Even Zeibart, well known for its single application rust proofing now offers an oil based formula to be applied annually.

Dealer and aftermarket wax based rust proofing can dry out and trap moisture against sheet metal and welded seems. The electronic black boxes that sell for hundreds of dollars and claim to prevent rust based on the science of cathodic protection are high tech snake oil with the lawsuits to prove it.

•    Modern Cars Are Not Immune:

A common fallacy is that modern cars don’t rust or rather don’t rust like earlier cars, as they are better made and receive better corrosion protection from the factory. There have been numerous recalls and safety warnings involving rusted suspensions, frames and electronic components for late model Asian and North American produced cars. The recalls run into the millions and are almost always targeted to “rust belt” States and Canada.

Perhaps the most egregious example is the recall and buy backs on Toyota Tacoma pick-ups that suffered terrible frame corrosion that could literally cause the vehicle to break in half.

True there is a greater use of alloys and galvanized metal however these too can be just as susceptible to the effects of brine solutions. Aluminum does not rust but salt and other de-icing sprays will cause oxidation and corrosion. Aluminum in cars is often in contact with different metals causing galvanic corrosion. The least noble metal in the combination i.e. aluminum becomes the anode and corrodes. In serve cases the aluminum components literally crumble into dust.

Galvanized steel has a thin coating of zinc only a few thousandths of an inch thick that protects it from rusting. The zinc is sacrificial and will corrode first protecting the steel. The life span of galvanized steel is severely reduced by stone chips on rough roads and exposure to aggressive chlorides or sulfides.

It is also the rust you don’t see that is killing your car. The widespread use of plastic bumpers, fenders and body cladding can hide corrosion on fender attachment points, welded seems on doors, trunks and hoods. Back to our awful climate, the freezing and thawing cycle moisture freezes expanding the area between spot-welds creating perfect areas for rust to grow, Just like that 71 Vega you drove in high school, sub-frames, floor pans and other underbody components of modern cars are just as susceptible to the effects of rust. If you are not in the habit of changing your own oil, underbody rust will on reveal itself when your feet get wet in the next rainstorm.

•    Preaching to the Choir:

I have owned and restored a number of vintage cars from the fifties through the seventies and have witnessed first hand the terrible damage that road salt can do. I once pulled a softball lump of salt from the rocker panel of a Riviera GS that had survived more than a few Canadian winters.  The entire floor and trunk pan had to be replaced due to severe rust perforation.

Perhaps the best example I can give for the efficacy of rust proofing is my long-suffering daily driver. The 1976 Lincoln Mark IV has been in my fleet for nearly two decades and has been sprayed every season. The Lincoln lives outside and is driven through out the winter months.
Under the layers of gooey black undercoating is a pristine chassis. Bolts and fasteners come off with ease and the car still has its original fuel and brake lines. The Lincoln has a patina of mild surface rust though that is due to the original paint having faded away years ago.

Last year I had the hood louvered by Oddball Kustoms, the metal work remains unfinished and has survived rust free with a little more than a coating of rust proofing. I also protect the car’s aftermarket wire wheels with a shot from an aerosol can. Washed off in the spring the delicate, thinly chromed wheels remain unmarked.

Driving your car in winter without rust proofing is a sure fire way to send it to an early grave. Perhaps you need to ask yourself how do highway contractors prevent their salt spreader fleet from evaporating into iron oxide…that’s right, annual oil based rust proofing.

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