Spring is just around the corner and I'm looking forward to spring cleaning – my car, that is. I'm the proud owner of a Kia Sportage and, since this was my first winter with the car, I want to get rid of any sign of the salt they spread so liberally over the roads in this part of the world before it has a chance to go to work. How can I be sure to get this stuff off places I can't reach during my normal wash/wax procedure? – Jeff in Sussex, N.B.
There are a couple of issues here.
The first is that the salt and the moisture-laden air in your part of the world have already begun to work their "magic" on any unprotected steel or iron parts of the vehicle.
The good news is that the use of bare steel or iron has been greatly reduced over the years. Most body panels are now made from double-sided galvanized steel – including those of your Kia that come from steel made at a plant the company owns in South Korea.
The galvanization process provides a protective layer atop the steel, which is good for decades if it is not compromised by scratches or a crash. More items like fasteners and suspension components are being made from aluminum and other alloys resistant to corrosion.
Having said that, there are a number of steel pieces inside and beneath your SUV made of steel that are exposed to the elements and thus easy prey to rust. I do not believe spraying a coat of oil or any supposed undercoating beneath the car is necessary. These surfaces are exposed to rain and drying air as you drive down the road. That combination will keep the demons at bay.
You rarely if ever hear of a vehicle rusting through from beneath since separate frames became the norm. The stamped steels used to make a chassis today are made of galvanized and protected steel.
A good drive on rainy day with lots of water on the road, especially one that has been recently flushed by a lot of rain, will rinse away much of the remnants of winter. Combine that with a slow drive through a high-pressure car wash – going slowly through the under-body spray portion will finish the job. After that wash clears any remaining semblance of wax off the car's finish, you are set to do your "spring cleaning," finishing up with a coat of fresh wax.
I came across your article on tire selection and found it cleared up some issues. I need to replace four tires on a RAV4 2009 265/65R/17. It came with H-rated tires so is it totally inappropriate or unsafe to go with the Michelin Defender or Michelin LTX MS/2, which are both T rated? – Salim
There's no problem with either of those tires.
The difference in ratings is inconsequential – sustained speeds of 210 km/h for the H-rated tires and 190 km/h for the Michelins.
These maximum speed ratings are obtained under laboratory conditions with the tires under load. I doubt you will ever encounter any experience where the difference in the two tires will come into play – at least not legally.
The ratings range from L to Y, generally following the alphabet with corresponding top safe speeds from 120 km/h to 300 km/h. The exception is the H-rated tire you speak of, which slots into that speed range chart between U and V in the ascending list.
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