Originally Posted By: SpitfireS
A while back I did read an article about small common rail diesel engines not producing much heat to get the interior up to a comfortable temp in cold weather.
It had to do with the efficiency of the engine (was/is pretty high) and no word about oil.
It's not just common rail engines. Both my wife's rotary pump and my unit injector diesels don't make much spare heat for several miles. Heated seats are fantastic in these cars.
In Chicago, this meant driving with your coat/hat/gloves on for the first 10 minutes or so. The oil is heated quite well - the engines are turbocharged and have piston squirters as well as an oil/coolant heat exchanger at the base of the oil filter housing.
In truly arctic weather (-20C and below), the coolant temperature would slowly drop as you idled at a stop light if you were running the heat. A buddy of mine who used to live in the superartic regions of northern MN sometimes had trouble keeping heat at all when traveling at speed (as well as keeping his fuel from gelling).
A couple things really helped cabin heat: blocking the front grille with pipe insulation helped retain more heat and installing a kilowatt tank heater in the coolant loop made for much warmer starts and easier driving.
And yet, both cars seemed to survive
somehow on synthetic oil...