2019 Suzuki Jimny (40,000 Miles): A Detailed Walkthrough of Inspection, Prep, and Protection

"Welcome back everyone. For those who are new to the channel, we're Rustec, one of the UK's highest reviewed authorised Dinitrol rustproofing centres, specialising exclusively in vehicle corrosion prevention, cavity wax treatments and underbody protection. Our goal is simple: to help as many vehicle owners as possible understand, prevent and manage corrosion before it becomes a serious problem. Whether you're planning on carrying out the work yourself or having it professionally treated, hopefully you'll find something useful in today's video. And if you've got any questions about rustproofing, corrosion prevention, products, application methods or your own vehicle, leave them in the comments section below and we'll do our best to answer them as quickly as possible. In today's video we're taking a detailed look at this 2019 Suzuki Jimny and showing you exactly how we inspect, prepare and protect it against corrosion."

Section 1 – Vehicle Arrival / Vehicle on Ramp

"Today's vehicle is a 2019 Suzuki Jimny with approximately 40,000 miles on the clock. What's particularly interesting about this vehicle is that the owner has had it from brand new and has looked after it extremely well throughout its life. This isn't a neglected vehicle. This isn't a vehicle that's been abused. And this certainly isn't a vehicle that's spent years sitting in a field. The reality is that corrosion can affect even well-maintained vehicles if preventative protection isn't carried out early enough. Like many owners, nobody ever advised him to rustproof the vehicle when it was new. Fast forward several years and we're now seeing significant corrosion development across much of the underside. Fortunately the chassis remains solid and the vehicle is still an excellent candidate for preservation. However, the amount of preparation required today is considerably greater than it would have been five years ago. If you're watching this and own a five to ten-year-old Jimny, there's a very good chance your vehicle looks remarkably similar underneath."

Section 2 – Stripdown / Post Stripdown Inspection

"With the vehicle safely on the ramp we can begin stripping down the underside. This involves removing wheels, liners, guards and various covers to gain proper access to the chassis and body. One thing we've learnt over the years is that corrosion loves hidden areas. It loves moisture traps. It loves seams. And it loves areas that rarely get inspected. As we strip this Jimny down we're paying particular attention to the chassis rails, body mounts, suspension brackets, crossmembers and enclosed structural sections throughout the vehicle. The Suzuki Jimny uses a traditional ladder chassis design which is fantastic for durability and off-road capability. However it also creates numerous locations where dirt, moisture and road salt can accumulate. As the inspection progresses it becomes immediately obvious that corrosion is far more advanced than on the newer Jimny we previously looked at. The corrosion is visible across much of the underbody. Fortunately the steel remains solid. We're not finding structural perforation. We're not finding severe metal loss. And we're not finding evidence that the vehicle is beyond repair. Instead we're finding widespread surface corrosion and corrosion scale."

Section 3 – Surface Preparation

"With the inspection complete we can move onto one of the most labour-intensive stages of the entire treatment. Surface preparation. Unlike a newer vehicle, this Jimny requires extensive corrosion removal before protection can begin. One of the biggest challenges we're facing is the factory-applied underseal. Many people assume factory underseal prevents corrosion indefinitely. Unfortunately that's simply not true. Factory underseal is designed to provide a level of protection during the manufacturer's expected service life of the vehicle. As vehicles age, moisture, impacts, temperature changes and road salt can allow corrosion to begin developing beneath the coating itself. One of the most common things we encounter is corrosion hiding underneath factory-applied underseal. From the outside everything can appear relatively normal. However once the coating begins lifting away from the steel, corrosion can often be found underneath. To expose the affected areas we're using needle scalers, wire wheels and mechanical preparation tools."

Section 8 – ML Cavity Injection

"With the corrosion stabilisation complete we can now move onto what many people consider the most important stage of the entire treatment. Internal cavity protection. One thing we regularly tell customers is that vehicles rarely rust from the outside in. More often they rust from the inside out. And that's because moisture has a habit of finding its way inside enclosed sections where it remains trapped for years. This Jimny is a perfect example. If the corrosion on the outside of the chassis has progressed to this level, there's a very good chance the internal corrosion is significantly more advanced. And that's something we frequently confirm using borescope inspections. The problem is that you can easily inspect the outside of a chassis. You can't easily inspect the inside. That's why internal protection is so important. To protect these enclosed sections we're injecting Dinitrol ML throughout the vehicle. Unlike heavier coatings, ML is specifically designed to creep. This allows it to penetrate seams, overlaps and hidden cavities where corrosion commonly begins."

Section 9 – Dinitrol 4941 Application

"With the cavity protection complete we can now move onto the final protection stage of the treatment process. Applying Dinitrol 4941. This is the stage most people associate with rustproofing because it's the visible protective coating applied to the underside of the vehicle. However, it's important to understand that the success of this stage depends entirely on everything that came before it. The inspection. The preparation. The corrosion removal. The drying. The masking. The RC900. And the ML cavity protection. Without those stages, even the best coating system in the world cannot perform to its full potential."

Section 10 – Demasking / Touch-Up Process

"With the 4941 application complete we can begin removing the masking materials. Whilst this may appear to be a straightforward process, it's actually an important quality control stage. As the masking is removed we're inspecting every area of the treatment. We're checking coverage. We're checking consistency. And we're checking that all protected areas remain clean and serviceable. One thing we've learnt over the years is that the difference between a good treatment and an excellent treatment is often found in the details. Anyone can spray a vehicle black. The finishing touches are where quality becomes obvious."