Using a Car Shampoo to Wash Your Hair – Should You Do It

When it comes to cleaning products to wash cars with, car shampoo is the ultimate. It’s arguably the most effective and safest cleaning product for your clear coat. However, many improvise by substituting hair shampoo for car shampoo, even if it’s not the safest practice. So, can you use car shampoo to wash your hair instead of hair shampoo?

Car shampoo should never be used to wash hair. Car shampoo affects the hair fiber’s integrity when used to wash human hair, as it is specifically formulated to remove grease and dirt from car surfaces. Car shampoo does not contain any conditioners, which are necessary to keep hair healthy.

The efficacy of car shampoo in cleaning stubborn car contaminants regardless, there are several reasons why you should not use it on your hair. Let’s take a more in-depth look and understand why you shouldn’t use car shampoos to wash your hair.

Can Car Shampoo Remove Dirt From Human Hair?

In general, car shampoo lacks the required abrasiveness to loosen oil and dirt from the scalp to be washed away by water. It is a car cleaning product that’s formulated to combat a unique set of car contaminants. Only hair shampoo is recommended for hair washing.

There are striking similarities between car shampoo and hair shampoo ingredients, but there are still some differences in their formulation that make them unlikely substitutes. Unlike dedicated hair shampoos, car shampoos don’t have conditioners as one of the active ingredients.

The lack of conditioning implies a lack of moisturization as you wash your hair because other shampoo ingredients reduce hair moisture.  

Comparing Car Shampoo with Hair Shampoo

When used for its intended purpose, car shampoo is a very effective cleaning product. However, it is grossly unsuitable for washing human hair. It is advisable to stick to shampoo made purposely for hair washing instead of car shampoo.

Although there are certain similarities between car shampoo and dedicated hair shampoo ingredients, there are many differences that make them unsuitable substitutes for one another.

The table below shows a comparison of hair shampoo and car shampoo, highlighting some similarities and differences between the common ingredients used to make both products.

Ingredients Car Shampoo Hair Shampoo
SurfactantsSodium Lauryl Sulphate, Coconut Fatty Alcohol Sulphate Sodium Lauryl Sulphate, Sodium Laureth Sulfate, 
Foaming AgentsCoco Diethanolamide Cocamidopropylamine Oxide, Coco Diethanolamide 
ConditionersNot present Present
ThickenersIndustrial SaltAmmonium Chloride, Hydroxyethylcellulose
PreservativesPhenoxyEthanolPotassium Sorbate, Sodium Benzoate


Both hair shampoo and car shampoo contain surfactants as active ingredients. Surfactants are the main cleansing detergents in shampoos. They are responsible for the breakdown of sebum, oil, dirt, and odor. Surfactants can also double as foaming and wetting agents.

Sodium lauryl sulfate and sodium laureth sulfate are the most commonly used surfactants in hair and car shampoo. For a thicker formulation and sud boosting, these surfactants are combined with a co-surfactant like coco diethanolamine.

Foaming Agents

While the foaming of a shampoo does not signify its washing effectiveness, foaming does help in the breakdown of grease, grime, and dirt present on cars and the hair. Besides, it makes for a nice visual effect, and it helps with lubrication when washing.

In addition to surfactants that have inherent foaming properties, popular car shampoos and hair shampoo formulas may contain ammonium lauryl sulfate, cocamidopropylamine oxide, or cocamide diethanolamine for improved sud production.


This is one ingredient that’s not common to both hair and car shampoos. Conditioner is a common hair shampoo ingredient. Why? It reduces friction that may occur between strands of hair as a result of the shampooing process.

Hair shampoo tends to reduce hair moisture, but the conditioner balances this effect by replenishing the moisture. Car shampoo, on the other hand, doesn’t contain conditioner. Foaming agents like coco diethanolamine and the occasional carnauba wax provide a smooth effect on car surfaces and prevent scratching.


Thickeners have very little or no effect on the functionality of either hair shampoo or car shampoo. However, they are common ingredients in both formulations for their thickening effect. Otherwise, the shampoos are likely to come out with a runny consistency.

Car shampoos are commonly thickened with industrial salt. They are used in small quantities because concentrated portions can activate rust on cars. Thickening agents like ammonium chloride or cellulose derivatives like hydroxyethylcellulose are commonly used to achieve thicker hair shampoo consistencies.


Without preservatives, shampoo formulations cannot combat bacteria formation, and they would have a very short shelf life. A wide range of preservatives is used in hair and car shampoos, from phenoxyethanol to potassium sorbate, sodium benzoate, and many more.

Key Takeaways

  • Car shampoo cannot be used to wash hair
  • Car shampoo does not contain conditioning ingredients
  • Hair shampoo cannot be used in place of car shampoo
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