Auto Undercoating

I recently took my car into have an oil change in southern California. The mechanic took the car in, raised the hood and took one look at the engine compartment and came quickly back out to see me with a very worried look on his face. He Said, “Sir, I think that someone has forgotten to tighten the oil filler cap on your engine, there is old oil all over the inside of the engine compartment“!

I had to explain to him that I was from Canada, eastern Canada were we put lot’s of salt on the roads in the winter time and this causes our cars to prematurely rust, sometimes as quickly as in 5 or 6 years. We spray the underside of the car and the engine compartment, but not the engine, with oil to protect the car from the salt and from rusting. He had never seen this before even though he had worked on many Canadian cars from western Canada. Apparently this process is not as popular in western Canada as it is in eastern Canada. ( If readers are familiar with this process in the US, please leave a comment in the comment section)

Anyway this conversation made me wonder if the $80 I spend every year getting my care coated with a special undercoat is really worth it or not.

Cars Driven in the South

Since we were in California, you get used to almost never seeing a car with rust damage on them. In fact you see many old cars on the roads, some of which are in pristine condition. Many cars require a new paint job because the direct sun has burned the paint or caused it to fade over the years, however the metal is still protected and not rusting at all. The only difference between our roads and southern California roads is that there is no salt spread on the roads in the winter time!

Where You Live

Where you live really seems to make a difference in the amount of salt on the roads. With temperatures that are just below freezing, salt spread on the roads will melt the snow quickly and keep the roads from icing. If the temperature is well below 20 degrees Celsius or  zero degrees Fahrenheit, salt does not work well. This may explain why the western part of Canada does not use as much salt as the eastern part of Canada and the north eastern portions of the US since their temperatures are cooler than us.

Salt on the Roads

The salt on the roads can be really heavy. If you have ever had to follow a salt truck you will know what we mean. It is just pouring out and it gets inside every nook and cranny of your car waiting to begin the process of rusting your cars steel frame. This is were auto undercoating can really help. If you spray your car thoroughly and get the oil into these small places, the salt cannot get in there and the oil will protect your car.  Spraying the car every year before the winter season begins will ensure that your car is well protected.

Waiting until after your car has been exposed to the salt may mean that it is not worth it to spray your car since the oil will lock in the salt mixture that is already on your car  in all of the wrong places. Get your undercoated every year in the fall before the first salt application on the roads.

How Long You Keep Your Car

It costs from $70 to $120 every year to have your car sprayed with under coating depending on were you go and the type of vehicle you drive. If you are only going to keep your car for 4 or 5 years then it may not be worth it to spend this money since most people buying a used car are more interested in whether the car is mechanically sound and how many miles are on it. Undercoating may make it more competitive in terms of pricing, however it is unlikely that you will get your money’s worth out of it.

On the other hand if you are one of these people who like to keep a car for 7 to10 years or even longer, then undercoating may be worth the money. Anything that keeps the salt away from the body of the car is definitely worth it. You just have to look at cars that have not been driven in winter conditions to see how well the body of the car stands up.

Stone chips are everyone’s menace, from cracked windshields to chipped paint. You can see the chips on the fenders and the hood of your car. You cannot see the stone chips on the underside and that is were the salt is going to get in and start the rust action on your vehicle as well. Undercoating every year will not only stop the entry of the salt, but will slow the rusting process down if does get started at these spots.

It is Messy

As my mechanic said to me, it looks as if the oil cap on the engine was off. There is no doubt that it is messy and every time you open the hood of your car you are going to get some on your hands. The point is that you should be careful especially if you are wearing good clothes, but it is there for a reason and that is to help you get the most out of your investment that you can. Some  people cannot stand their car being coated with oil and if you look at any show type car, there is not a spec of oil on them. However if you use your car every day during the winter you want all of the protection you can get, mess or no mess.


We talked about whether auto undercoating enhances the sales price of your car when you sell it. Most people think that it helps to sell the car, however you probably will not get much more money for the car, undercoated or not providing that there are no rust spots showing anywhere on the car.

Once rust begins to appear, then the value of the car drops very quickly. In this respect, if applying under coating prevents rust from appearing or at least delays it, then the increased price you can get for your car definitely pays for the cost over the years you will have had the car.

We have seen numerous comments on various web sites for and against auto undercoating.  We would appreciate yours as well on this post.

Tags: , , , ,

You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

AddThis Social Bookmark Button

Leave a Reply