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Hi Rob

Our daughter lives in a remote northern community. She and a few others were leaving recently, when it was really cold (approaching -45C). She was advised to put cardboard over the front end of the engine to stop the rad from freezing. She asked and I suggested that if the anti-freeze could handle the temperature, cardboard was unnecessary and too much could cause problems. Who's right?

Danielle B.

Danielle, the brochures try their hardest to illustrate the extreme weather testing that vehicles are exposed to. However, nothing replaces real-life.

At face value, a car owner should be able to trust the manufacturer to supply a vehicle that can put up with anything mother nature can throw at us, but these tests are done with brand new vehicles and a team of engineers at their beck and call.

Even though many of these test procedures are conducted in bitter winter conditions in places such as Greenland, Nunavut, Sweden etc., they do not account for everyday driving and the normal aging of a vehicle.

For extended periods of time at -45C, I would be tempted to place cardboard in front of the radiator myself.

Here's a tip: Look for the NORMALS. That is, if you have a temperature gauge, does it reach its normal position? This should be the halfway mark of the gauge or at least 95° Celsius. Also monitor the temperature coming from your heater. If you find that the temp is less than you normally experience, you should use the cardboard.

Not only will the cardboard make the cabin more comfortable for you, your engine will thank you because it needs to run at, or around 100°C. The reason: this is the temp that the engine was engineered to perform at to meet fuel economy and emission regulation numbers. The other reason for this benchmark temperature is that water boils at 100°C. This ensures that all water vapour that collects inside the cavities of the engine (and transmission) gets "boiled" out. Leftover water is one of the contributors to sludge, not to mention interior corrosion of the engine and transmission. This is also the reason many publications tell us to minimize short trips. The engine does not have time to reach 100°C for a long enough period. Usually 20 minutes is needed to boil off the internal condensate.

That said, it is important to remember that the cardboard is there because as the outside temperature rises, you must remove it. if not, you run the risk of over-heating the engine.

So, Danielle, you're both right - to a point. Try my tip, and if needed, the corrective action will be to cut up that packing box and tuck it behind the grill.

E-mail Rob your automotive questions: GlobeDrive@globeandmail.com

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