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How to Tell Its Rot or Surface Rust

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How to Tell Its Rot or Surface Rust

Created on: 2017-06-22

How to tell the difference between frame rot and surface rust.

  1. step 1 :Identifying Rot or Surface Rust
    • Tap on the rust spot with a screwdriver
    • If the spot is solid, it's surface rust
    • If the rust breaks off, it's rot
    • Bubbling paint also indicates rot

Tools needed for replacement

  • Screwdrivers & Related

    Flat Blade Screwdriver

Installation Video
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Hi, I'm Mike from 1A Auto. We've been selling auto parts for over 30 years. We're dedicated to delivering quality auto parts, expert customer service, fast and free shipping, all backed by our 100% satisfaction guarantee. Visit us at, your trusted source for quality auto parts.

You may see a couple of different types of rust on your vehicle. This here, behind the wheel – this Suburban has over 140,000 miles on it and it would appear that some portion or a good portion that 40,000 miles was on dirt or gravel road.

You see that there's some rust here but this is just surface rust. If I press on it with a screwdriver and if I tap on it, it's good and solid. Basically all that's happened here, and it has been painted over, is the wheel kicked up rocks, they chipped away the paint eventually and this has stayed clean and fairly dry so you've got a little bit of surface rust, but this can easily be sanded down and touched up and repainted.

Back here, we've got a different situation going on. Rear wheel, you're in front of the wheel, and you can see paint bubbling, which means something is going on inside. Also, you can see it. There's already a hole here from where I tested it earlier. But if I press on this with my screwdriver, it goes right through there. The metal is very weak. This is rot through. It's important to address this but also you can check out our other videos to address the cause. You want to find out why there's buildup behind this. You want to alleviate it and clean it out and keep it clean.

Thanks for watching. Visit us at for quality auto parts, fast and free shipping, and the best customer service in the industry.

Tools needed for replacement:

    Screwdrivers & Related

  • Flat Blade Screwdriver

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