You choose a car shampoo based on what your car needs. For the regular weekly wash, pick a pH-neutral, coating-safe shampoo: it cleans without attacking your wax or coating. If you want to add gloss and protection while you wash, choose a ceramic-effect or wax shampoo. A strong, alkaline shampoo you only use for a heavily soiled car or to strip old wax before a new coating. Always dilute according to the manufacturer and wash with the two-bucket method to avoid scratches.
pH-neutral versus strong cleaning
The biggest difference between shampoos is how strongly they clean. A pH-neutral shampoo cleans without attacking the existing protection, so your wax or ceramic coating stays intact. That makes it ideal for the regular maintenance wash. A strong, alkaline shampoo pulls grease and heavy dirt loose, but strips wax along with it and loosens sealants faster. You use that in a targeted way: on a heavily soiled car or deliberately to bare the paint before applying a new coating. For most people a pH-neutral shampoo is the safe default, a strong shampoo a tool for special jobs. A nice pH-neutral all-rounder is the Koch Chemie AS Car Shampoo.
Ceramic-effect and wax shampoo
Some shampoos do more than clean: they lay down a thin layer of protection and gloss while you wash. A ceramic-effect shampoo contains SiO2 that makes water bead off and boosts the gloss, and that you build up again with every wash. A wax shampoo does something similar with a carnauba or polymer component for a warm glow. Both are ideal if you want to keep your protection topped up between major sessions. The Koch Chemie CES Ceramic Effect Shampoo is a strong example of this; if you mainly want extra gloss, a gloss shampoo such as the D-CON Mint Splash is a pleasant choice.
Concentrate and dilution
Most good car shampoos are concentrates that you dilute heavily, depending on the brand often between 1:100 and 1:200. That seems like little product per bucket, but that is exactly the point: a small dose cleans fine and a bottle lasts a long time, which keeps the cost per wash low. Stick to the manufacturer dilution, because too much shampoo causes streaks and waste, too little gives insufficient lubrication. Measure the dose instead of guessing, so every wash is even.
How to wash with shampoo
Pre-rinse the car thoroughly first, preferably with a layer of snow foam, so you remove most of the sand and dirt before you put the mitt on the paint. That limits the risk of scratches.
Dilute the shampoo according to the manufacturer in a bucket of water. Preferably fill with lukewarm water, which activates the shampoo and gives more lubrication and foam.
Wash with the two-bucket method: one bucket with shampoo and a separate bucket with clean water to rinse your wash mitt. Work from top to bottom and rinse the mitt after each panel, so you do not drag dirt around.
Rinse the car well and dry it immediately with a plush drying towel. That prevents drying water from leaving minerals behind as water spots.
Which one suits you
Regular weekly wash on a waxed or coated car: a pH-neutral, coating-safe shampoo.
Adding gloss and protection while washing: a ceramic-effect shampoo or a wax shampoo.
Heavily soiled car or stripping old wax before a new coating: a strong, alkaline shampoo.
In doubt? Choose pH-neutral. That is safe on almost any car and the most used choice for maintenance.
The shampoo wash is the second step in a safe washing routine. Start with a pre-wash: read how to set that up in the guide on using snow foam. See the full range in the car shampoos category.