In ON, what should I know about rust-proofing for car loans?

When considering rust-proofing for a car loan in Ontario, it's crucial to weigh the actual benefits against the added cost. Modern vehicles, especially those manufactured for the Canadian market, come with advanced factory corrosion protection, including galvanized steel and multi-stage paint processes, often backed by a manufacturer's perforation warranty typically lasting 5-7 years. However, these warranties usually cover rust that perforates the body from the inside out, not surface corrosion or damage from stone chips.

Ontario's harsh winters, with extensive use of road salt and brine, present a significant challenge that can accelerate corrosion, particularly on undercarriages and exposed components. While aftermarket rust-proofing, such as oil-based or wax-based treatments, can offer an additional layer of protection, adding it to your car loan significantly increases the total amount borrowed, leading to higher monthly payments and more interest paid over the loan's term. As of 2025, dealerships frequently present these as high-margin add-ons.

For consumers, this matters because you need to assess if the potential long-term benefits of enhanced vehicle longevity and resale value, particularly if you plan to own the car for eight years or more, justify the immediate financial burden. Understand that lenders do not typically require rust-proofing for loan approval. It's an optional purchase that should be carefully considered based on your ownership plans, the vehicle's factory warranty, and your budget, rather than being an automatic inclusion in your financing.