I travel a lot so my truck sets at the airport often.In the past,after being gone for a week or so I would kick the heaters on 2 or 3 times,then start the truck.I would then set and freeze for about 10-15 minutes and drive away still freezing.They have a new section at the parking lot where diesels can finally plug in.Does anybody know of any bad effects from leaving your truck plugged in for a week or longer?Might have to buy a fancy timer that will continue to turn itself on and off until unplugged.

 

I have mine on a timer because it's sits quite a bit at home. I have an onboard battery maintainer plugged in also. Make sure it's at least 15 Amp timer.YMMV

 

you should be fine i used to do it all the time for many weeks when i lived in Alaska, however i have seen some vehicles malfunction and catch fire... very rare but it can happen! good luck