Acidic vs Alkaline Car Shampoo: What's the Difference?
Most maintenance shampoos are pH-neutral, but some are deliberately acidic (pH < 6, often to boost water-beading or freshen a coating) or alkaline (pH > 8, for stronger cleaning of heavy grime). Acidic shampoos can enhance hydrophobics and help with light water spots but should be rinsed promptly; alkaline shampoos cut grime harder but can strip wax/sealant if used too strong. For coated or waxed cars, neutral is safest. Below are catalogue shampoos grouped by where they actually sit on the pH scale.
Last updated: 2026-06-19 · 14 products · Data: manufacturer documentation & SDS, via the Find Your Detail catalogue.
Acidic shampoos (pH ≲ 6)
| Product | Brand | pH | Dilution |
|---|---|---|---|
| Demineralizing Shampoo | clean | 1 | 1:256 |
| Boat Descaling Wash | koch chemie | 1 | 1:200 |
| Acid Shampoo A | koch chemie | 1 | 1:33~1:66 |
| S-Prewash 2.0 | luminus | 2 | 1:200~1:300 |
| Prolim PH2.8 | nihachi pro | 2.8 | 1:50~1:100 |
| PURIFICA - Acid decontaminant shampoo | labocosmetica | 3 | 1:400 |
| Sour Shampoo | good stuff | 3 | 1:200~1:400 |
Alkaline shampoos (pH ≳ 8)
| Product | Brand | pH | Dilution |
|---|---|---|---|
| Polar Wash | auto glym | 12 | 1:1 |
| Citrus Wash & Gloss | chemical guys | 12 | 1:600 |
| Decon Soap | armour detail supply | 12 | 1:192-1:512 |
| Adam's Proline RENEW - Decon and Strip Soap | adam s polishes | 12 | 1:213~1:320 |
| Cleanion Pro | nasiol | 12 | 1:500 |
| Cleanion Pro Marine | nasiol | 12 | 1:500 |
| Hard Wash | detail co | 11 | 1:10 |
FAQ
Is an acidic or alkaline shampoo better?
Neither is 'better' — it depends on the job. Neutral for routine coated/waxed cars, mildly acidic to boost beading or tackle light water spots, alkaline for heavy grime on unprotected paint. Match strength to the dirt, not the other way around.
Will an alkaline shampoo strip my wax or coating?
A strong alkaline shampoo used frequently can shorten wax/sealant life and dull a coating's beading. Occasional use is usually fine; for regular washing of a protected car, stay neutral.
Sources
The pH and dilution figures in this guide are each product's own manufacturer documentation and Safety Data Sheet (SDS) as recorded in the Find Your Detail catalogue — click any product above to open its source page and full details. Values are maker-stated/best-case; real-world results vary with technique, water hardness and conditions.