Underbody Coating and Rustproofing Hamilton

About This Service

Stop Rust Before It Starts

Kiwi roads are hard on a chassis — salt off the coast, gravel inland, constant moisture under floor pans and inside box sections. Underbody coating is the cheapest insurance policy your car will ever get. We strip, treat, and coat the underside with proper automotive-grade product that flexes with the chassis instead of cracking off.

Underbody, chassis rails and floor pans
Cavity wax for sills and box sections
Compatible with later WOF rust repairs
Quiet ride bonus — coating dampens road noise

Underbody Wash

Underside washed and dried before any product goes on.

Treat and Coat

Rust converter where needed, then automotive-grade coating applied evenly.

Cavity Wax

Inner sills and box sections injected with cavity wax through factory access points.

Masked Properly

Exhaust, brakes, driveshaft and sensors masked — no overspray where it doesn't belong.

Lift and Inspect

Vehicle up on the hoist. Existing rust marked and noted before treatment.
Wash and Dry

Underside cleaned and dried — coating won't adhere to dirty steel.
Treat

Surface rust treated with rust converter to stop further oxidation.
Coat and Wax

Underbody coating applied. Cavities injected with wax. Dried and inspected.

Same underbody cleaned, treated and freshly coated

Vehicle underbody showing surface rust and old flaking coating

Before After

Full Underbody Reseal

Years of road grime and surface rust across the floor and chassis. Cleaned back, treated, and given a fresh rubberised coat to keep the Waikato wet out for good.

Rust Treated
Rubberised Coat
Full Underside

Chassis rails sealed with a protective underbody coat

Bare chassis rails after repair, before coating

Before After

Chassis Rail Protection

Bare rails after repair, sealed before they ever saw a wet road — the cheapest rust job is the one you do early.

Post-Repair
Sealed

Wheel well coated with a tough protective layer

Wheel well with chipped paint and early surface rust

Before After

Wheel Well & Arch Coat

The spots that catch the most stone-chip and spray, built up with a tougher coat to take the hits.

Stone-Chip Zone
Heavy Coat

When should I get underbody coating done?

Before rust appears. Best time is on a newer or recently-acquired vehicle, especially if you live near the coast or drive on metal roads. Older vehicles benefit too — just expect rust treatment to be part of the job.

Will it pass WOF if I get it coated?

Yes — proper underbody coating helps a WOF, not hinders it. A WOF tester needs to see structural metal isn't hiding rust, which we don't do; we treat what's there first.

How long does it last?

Properly applied automotive coatings last many years. We recommend a quick inspection every 2–3 years to touch up any damaged spots from stones or impacts.