I live in western MA. I have a 2016 Z71 long bed, I was originally going to order the truck, but at the time there was no definitive delivery date when ordering . After a 4 month search I found the exact truck I wanted in the neighboring state of VT. The VT dealer was located about 2hrs. from me, so I went to my local dealer to see if they could arrange a trade with the other dealer, which they did. When the truck was delivered to my local dealer they sent a kid out to pull the truck in for detailing , the kid started the truck and immediately shut it off, returned to the shop and told the shop manager that there was something seriously wrong with the truck. He stated that it sounded like it had a bad motor... LOL, he had no idea they even made a diesel version of the Colorado.
Anyway, what we discovered after delivery was that the truck had never been spec' with a block heater. I was told at this point it would be roughly $300.00 to install it. At the time my wife had a 2014 Volkswagon Passat TDI without a block heater that had successfully started at -21 (real temp, not windchill). So I opted to forgo the block heater.
The last 10 days in Western MA the temps have been below 0 every night, Saturday evening being the coldest at -11 (-11 real temp, wind chill -23) I went out, cycled the glow plugs 3 times and the truck started with no issues, not even a rough idle. I do not use my remote start when temps are extremely low because I want to cycle the glow plugs 2 or 3 times. I also use an anti-gel when filling the truck in the extreme cold.