From Tar to Tech: How Undercoating Evolved to Protect the Modern Vehicle

Rust is the silent killer of vehicles. It creeps in, corrodes structural integrity, and destroys resale value — often before the average driver even knows it’s there. But the fight against rust isn’t new.

Since the early days of the American highway, mechanics, automakers, and chemical engineers have been waging a war beneath our vehicles. The weapon of choice? Undercoating — and it’s come a long way since its gritty, tar-like beginnings.

The Origins: Tar, Asphalt, and Good Intentions

In the post-WWII era, car ownership exploded, and so did road infrastructure. But as drivers ventured farther — especially into the salty, snowy Northeast — rust became a real issue.

The early solution was simple: spray a tar- or asphalt-based coating on the underbody. These thick, sticky compounds created a physical barrier between the metal and the elements.

It worked… for a while. But these coatings were heavy, messy, prone to cracking, and nearly impossible to remove for service or inspection.

The 1970s–1980s: Rustproofing Goes Mainstream

As rust complaints grew, car dealerships and service centers began offering “rustproofing packages.” These typically involved:

• Drilling access holes into body panels
• Spraying waxy or rubberized coatings into cavities
• Applying thick layers to wheel wells, fender seams, and undercarriages

Some worked — many didn’t. The problem? Many of these services were more cosmetic than protective. Worse, some early products sealed in moisture, accelerating rust.

The 1990s–2000s: Automakers Fight Back

In response to mounting warranty claims and consumer pressure, manufacturers began improving factory corrosion resistance by:

• Using galvanized steel
• Improving drainage and seam sealing
• Offering rust-through warranties

While this helped, factory protection had limitations — especially for trucks, vans, and vehicles used in rougher conditions. That’s where aftermarket undercoating services remained essential — when they were done right.

The 2010s–Present: Science Meets Application

Today, the best undercoating products aren’t tar-based at all. They’re engineered to:

• Penetrate seams and cavities
• Remain flexible and breathable
• Resist salt, moisture, and road abrasion
• Work in tandem with factory coatings — not against them

Modern products like Noxudol 900 and fluid-based options like NH Oil represent a new generation: smarter chemistry + better application = real protection.

Where We Are Now

At APS in Fairfax, we’ve applied thousands of undercoating treatments across Northern Virginia and beyond. We’ve seen the damage that older vehicles suffer — and we know how far the industry has come.

Today, we apply undercoating only after cleaning, prepping, and inspecting each vehicle. We use the right products for the right application — not a one-size-fits-all mess.

Looking Ahead

Undercoating isn’t just for beat-up trucks or salty winters. It’s a proactive, long-term investment in your vehicle’s structure, safety, and resale value.

As this series continues, we’ll explore how different coatings work, what went wrong in the past, and how to protect your car or truck from the ground up — literally.

Schedule Your Undercoating Service

Call: (703) 591-0900
Address: 3170 Draper Drive, Unit #8, Fairfax, VA 22031
Book online: apsrustandtint.com/schedule

Trust undercoating that’s done the right way — not the outdated way.