AUTOMOTIVE
How to Clean and Maintain Your Vehicle’s Undercarriage
Salt, slush and temperature swings can be hard on the underside of your vehicle. Here’s how to protect it.
By Jeremy Freed | Illustration by Guilherme Henrique
Most drivers understand the importance of washing a vehicle’s exterior. However, overlooking its underside can be a costly mistake due to the road salt, slush, and freeze-thaw cycles that come with Canadian winters.
Road salt and de-icing treatments are important for road safety, but they are highly corrosive to your vehicle’s metal parts. On top of this, temperature fluctuations cause moisture to expand inside tiny surface imperfections, potentially cracking protective sealants. This can allow rust to creep in. Further complicating matters is the fact that, unlike your car’s painted surfaces, you can’t spot rust or corrosion developing on the frame, exhaust, brake lines, fuel lines, wheel wells and suspension without getting underneath for a closer look. (A task best left to your mechanic.)
Here’s how to take care of your vehicle’s “under anatomy.” Firstly, have your vehicle treated with an anti-rust undercarriage coating — a solvent-free petroleum-based formulation — either by your local auto shop or a specialist. (CAA members save $10 on Krown Rust Control.) If you live in an area where road salt is used, you should have your vehicle treated once a year, ideally in early fall. Otherwise, every year or two is fine. Treating your new vehicle is a good idea, before it has its first encounter with sand and salt. The second thing to do is thoroughly wash your car’s underside every two weeks, either at home using a hose and an undercarriage wand or at a do-it-yourself “in-and-out” car wash. If you opt to do it at home, check your local bylaws, as many Canadian municipalities prohibit washing vehicles on driveways or streets, where soap and chemical runoff can enter storm drains. In these areas, rinsing thoroughly with plain water is a safe and effective alternative — the goal is to remove as much salt and sand as possible. If you choose a commercial car wash, select a touchless one that includes an undercarriage spray.
All of this may seem like a hassle, but it’s a relative bargain compared to the potential ravages of unchecked rust. Your vehicle will look great, too. CAA
Treating your new vehicle is a good idea, before it has its first encounter with sand and salt.
Drip Dos and Don’ts
A stain on your driveway can be a warning sign.
Small drips or stains on your driveway or garage floor can indicate potentially serious issues. Find out what each colour could indicate.
Brown If it’s brown and under the engine, it’s likely oil.
Red or pink Fluid in these colours typically points to a transmission or power steering leak.
Green, orange or pink (and sweet-smelling) It could be a coolant leak. Make sure to keep pets well away from it, as coolant is highly toxic to cats and dogs.
Light yellow or amber If you see drips in this colour near the wheels, it could be brake fluid. This can be a critical safety issue, and the vehicle should be towed, not driven, to the shop.
Clear water If it’s hot outside and you notice clear water dripping from the engine area, however, don’t panic — it’s just condensation from your air conditioner. When in doubt, leave a piece of white cardboard under the drip overnight, and, if the results suggest an automotive fluid leak, see your mechanic as soon as possible.
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