The Ultimate Guide to Automotive Glass Clarity and Protection (Jan 2026)

Never clean glass that is hot to the touch. In 40°C weather, glass temperatures can reach 70°C. Move the vehicle into a garage or under a carport and allow at least 30 minutes for the glass to cool. If the cleaner dries instantly, it will leave chemical streaks that are harder to remove than the original dirt.

Before applying any liquid, use a soft duster or low-pressure compressed air to remove loose red dust or sand. If you apply a wet cloth directly to a dusty window, you create an abrasive 'slurry' that can cause micro-scratches, especially on softer aftermarket window tints.

Lift the wiper arms and inspect the rubber squeegees. Clean the blades with a damp paper towel and a small amount of glass cleaner. If the blades are cracked or leaving a 'graphite' residue on your fingers, they must be replaced, or they will immediately re-contaminate your clean glass.

If using a concentrate (like 3D Glass Cleaner), mix precisely at the manufacturer's recommended ratio (usually 1:10 or 1:50) using distilled water. Over-concentrating the solution increases the surfactant load, which is the primary cause of 'ghosting' or streaks.

Rinse the exterior glass with a steady stream of water to dislodge salt crystals and heavy grit. For coastal vehicles, this step is vital to prevent 'scouring' the glass surface during the agitation phase. Pat dry with a dedicated drying towel.

Divide large areas like the windscreen into four manageable quadrants. Working on the whole window at once in high temperatures leads to the cleaner drying before you can buff it, resulting in uneven clarity.

Mist the glass cleaner onto your first waffle-weave towel rather than spraying directly onto the glass. This prevents 'overspray' from landing on leather dashboards or plastic trim, which can cause spotting or discolouration over time.

Scrub the quadrant using firm, overlapping vertical and horizontal motions. Do not use circular motions; linear strokes ensure total coverage and make it easier to identify the direction of any remaining streaks later.

Use your finger inside the towel to get deep into the corners and along the rubber seals. This is where red dust accumulates most. Ensure you don't pull dirt from the seal back onto the clean glass.

Immediately switch to your second, completely dry microfibre towel. Before the cleaner evaporates fully, buff the surface using light pressure. This towel picks up the suspended contaminants and the remaining surfactant film.

For the interior, especially if you use interior protectants, use a 1:1 IPA/water mix first. This cuts through the oily film that builds up from plastic outgassing and air conditioning use, which regular glass cleaners often just smear around.

Wind the side windows down 2-3 centimetres. Clean the very top edge of the glass that sits inside the weatherstrip. This often-overlooked area collects a line of grime that will smear down the window every time you roll it up and down.

If the glass still feels rough after cleaning, use a clay bar with glass cleaner as a lubricant. Glide the clay over the surface until the 'grabbing' sound stops. This removes embedded metallic particles and stubborn sap.

Inspect the glass from multiple angles. A pro tip: wipe the exterior glass with vertical strokes and the interior with horizontal strokes. If you see a streak, the direction of the streak tells you instantly whether it is on the inside or the outside.