Does undersealing stop rust that has already started?

On its own, no. Coating over active corrosion seals damp against the steel and the rust keeps working underneath, out of sight. Undersealing only stops rust when the corrosion is dealt with first.

What has to happen before coating

• Underside washed and degreased
• Flaking coatings and loose scale stripped back
• Perforated or weak steel cut out and welded
• Remaining surface corrosion treated
• Box sections cavity waxed from the inside

Surface rust versus structural rust

Light surface rust on sound steel can be cleaned, treated and coated. Steel that is perforated, flaking in layers, or soft to a scraper is structural and needs welding first — no coating fixes it.

How to tell which you have

Sound steel rings when tapped; rotten steel gives. If you are not sure, get it on a ramp. We do a free chassis check and send you photos of what we find.

Send underside photos to 087 919 2193 on WhatsApp and we will tell you honestly which category your vehicle is in.