i feel pretty dumb asking this...
 

but do all of the cr's have a block warmer? im in texas and it was 81 here yesterday but dropping down to the single digits tonight.

yes they are all equiped with the heater itself but ya have to but the cord

the heater in in the frost plug right behind the oil filter

best buy on a cord that I know of is Genos Garage

Ebay has them for around $30, simple install.

I started my 05cummins at -30 without being plugged in, i dont even begin to think about plugging in until its -10:tu:

That's all fine and dandy without plugging it in, but it makes things so much easier for the engine to turnover when it's plugged in. Just my .02

how do you know if your plug is working right?
i plug mines every day but i dont see any difference in the temp gauge whe i started in the morning.

lol mine doesnt either i always wondered the same thing too its hard to tell cuz the cr start and run really good in the cold.

i left the cord out when i put my engine in, and deleted my IAH.

it dont get that cold down here

On mine you can tell the block heater is working because after being plugged in the squiggly wait to start light is not on in the morning and if I don't plug in and the manifold temp is below 40 the squiggly line is on