Block Heater
 

Anyone install one of these in their Cherokee? I just moved to Montana and will need one pretty soon. Thanks. Coach.

I know there are several kinds.. the most efficient as well as the ones from factory mount in place of a freeze plug. Me personally, being in northern VA, went on ebay and found one that magnetizes against your oil pan and warms the oil to some 120* or so. Basically anything that will help the oil cycle faster is always good for your engine. There is something you can get for batteries as well that help with cold starts.