Hey guys, I've got an 06 auto that just went through its first cold snap. Temps were -25 to -32 C here (Calgary) last week (touching -40 with windchill) and my truck started okay (plugged in) although it turned over slow and sure was rough when it caught.

What didn't seem right to me was the water temp I was seeing when driving - took a long time to warm up and when it did get to its normal operating point (just touching the 95C mark on the gauge) it would drop like a stone when I stopped. I could literally watch the needle swing down while sitting at a stoplight, and when I left the truck running (on high idle) for several minutes the water temp needle had dropped all the way to the bottom of the normal range.

I've got ~1/2 the rad blocked with cardboard. Now that the temps are getting up near freezing again, the truck warms up as expected. My daughter sat in her carseat wrapped up in a blanket most mornings asking me why the truck was so cold...

Is this the norm for these trucks? Seems to me that the temp is getting too cold too fast.

 

The rad is huge and has good cooling for towing. Cover up the entire rad when really cold, but try to attach the cardboard to the inside of the grill instead of directly over the rad. This way, if it gets to warm and your fan does kick in, there is still the availibility of air movement through the rad and far easier on the fan clutch bearing.

 

Thanks Festus. My next attempt was going to be covering the whole rad but you've got a good point about leaving a gap between rad and cardboard. Simply seemed to me that the truck was running too cool.

 

I have the same problem with my '06 when coming down a long canyon road in the cold. The temp drops so much it barely puts out any heat inside. To make it worse, you can't use the defroster with recirculated air so it gets even colder at the vents.

 

At least it isn't just me. It's warm enough this week that all the snow is turning to slush - good time to button up the grille for the next cold snap.

 

Or if you want you can cut out a hole in the middle of the cardboard that's the size of the fan hub. That'll allow plenty of air to the fan hub but still block the rest of the radiator.