Car Wash Comparison: Which Type of Soap is Best for Your Car?

Published by on . Updated on 18 May 2020

Spray Bottles(Photo Credit: Public Domain Pictures)

Regular car washes are a must for any driver—it's much more than just keeping your vehicle looking good! Neglecting to wash your car will allow dirt and dust to collect, which over time wears away your paint coat, making your car vulnerable to rust.

If that gets severe, you may have to go to a mechanic, where rust repairs can cost up to $100! So don't forget to treat your car with a good wash after a long week on the road. Most drivers do a DIY car wash at home, which will get the job done, but not everyone knows the best way to do it. One of the biggest questions is—do we really need to use professional car shampoo to clean up our cars? Or will home dishwashing soap do? Or even homemade washing solutions, for the hardcore DIY drivers? Today, we compare the three to tell you which one is actually best for your car!

1. Cost

Money 1005465 1920(Photo Credit: Pixabay)

Cost is, of course, one of the biggest considerations when thinking about what car wash solution to use. Most people would think that proper car shampoo is more expensive than dishwashing liquid, but that's actually not true. Carwash shampoo can cost $8 to $20 for a 64oz (about 1.8 litre) bottle, while dishwashing soap costs about $12 for the same amount. This puts them roughly on par in terms of cost.

The cost of homemade solutions, of course, depends on what you choose to put in it. Most DIY car solutions are the same as a dishwashing or car shampoo solution, but with baking powder or vinegar added in to strengthen it. This means that the price will be pretty much the same as well, so in the area of cost, all three types of carwash solution are more or less equal! Any price difference will probably be due to your choice of the brand.

Verdict: As far as cost goes, all three solutions are more or less the same.

2. Cleaning Dirt

Wash A Car 1822415 1920(Photo Credit: Pixabay)

On to another important concern: which type of carwash solution is best for actually getting the job done? After all, the main point of washing your car is to get the dirt off. Car shampoo and dishwashing liquid are both definitely able to wash off dust and daily dirt. However, when it comes to stains like bugs or bird droppings, it does take some extra to get them off. This is where dishwashing liquid has an edge. It's designed to remove thick grease and food stains, which means that it's more aggressive and effective in removing stubborn dirt.

Homemade solutions are also good for cleaning problematic stains if they've got baking powder added. Baking powder is a powerful cleaning agent that causes dirt to dissolve, so it's as good, and maybe even better than dishwashing soap in cleaning stubborn dirt. So in the area of getting dirt off the car, a homemade solution of dishwashing liquid and baking powder would be most effective, followed by just dishwashing liquid, followed by carwash shampoo. This is not to say, however, that car shampoo will be unable to get off difficult stains, just that it may take more effort and time. The other two options will cut through stains more easily.

Verdict: For cleaning dirt, a homemade solution of dishwashing liquid and baking powder is the strongest, followed by dishwashing liquid alone, followed by car shampoo.

3. Paint Protection

Porsche 911 1373868 1920(Photo Credit: Pixabay)

Finally, which type of carwash solution is best for your car's paint? No driver likes to see scratches their precious paint job, and you don't want to end up unknowingly hurting your car. Well, in the aspect of paint protection, there is no question that car shampoo is the best. Car shampoo is specially designed to clean cars, so it won't damage your paint or waxing. It contains a lubricant that helps to clean off the dirt easier, without requiring the kind of rough constant scrubbing that causes damage. When you use car shampoo, you can be assured that your paint remains safe under the wax.

Dishwashing liquid, on the other hand, is likely to be too harsh for your car's paint. Even though it is very effective in removing dirt, its strength comes from its abrasive nature, which means that it will also scratch off your waxing over time. Once your wax is gone, your paint will be exposed and vulnerable, and continued washing with dishwashing liquid is likely to cause scratches and swirls as the harsh soap breaks down your paint.

Baking powder has the same problem. Even though its abrasiveness makes it a good cleaning agent, it's also extremely harmful to your car's wax and paint. If you've been using dishwashing liquid or a baking powder home-mixture to clean your car for a while, you might notice that your car body is less shiny than before, and may even have some patches where the paint looks damaged. You may want to consider getting a touch-up and re-waxing if this is true for you. So even though dishwashing liquid and baking powder solutions are good cleaners, their strength makes them harmful to your car's paint. If you really do want to use them, it might be better for spot cleaning, if you have particular stains that you can't get off.

Verdict: Car shampoo is the only one that protects your car, the other two are damaging to your paint and should only be for spot cleaning if necessary.

So what's the final verdict?

In terms of cost, the three types of carwash solution are surprisingly close. Car shampoo may seem more expensive at first, but in the long run, it evens out. Dishwashing liquid and home solutions do provide stronger cleaning ability which makes your car wash session easier, but this cleaning ability also means that they harm your wax over time, which will result in more headaches when your paint is exposed to all kinds of damages. To sum up, car shampoo is most likely still the best choice—it may be less efficient if your car is particularly dirty, but the effort saved is not worth the damage that dishwashing liquid and home solutions may cause to your car overall.

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