Temp.

[david]

Well i took delivery of my new 05 crew cab long bed today!!!!
The only thing that bugs me is if i run 55 mph the temp. stays at 190 , if i zip it up to 70 mph for a few min. it jumps to 215*.
Drop back to 55 and it goes down.
Is this normal????????
What a great truck!!!!!!!!!!!
David

[DarylB]

What's the outside air temp? Does it do this consistenly all the time? I know it's in the 20's here in AR now. It would seem normal for the temp gauge to fluctuate more in colder weather from the thermostat opening/closing, but not everytime you get above 55mph. My 2002 goes from about 180-195 when on the highway (in cold weather). It sometimes moves lower after highway driving in the cold and it stops. Someone with an 04 or 05 might want to chime in.

[More Power]

Your LLY temp readings are probably normal. The LB7 does basically the same thing in cool/cold weather.

During the year or so runup to production, GM tested the Duramax in both very cold and very hot environments. Quite a bit of effort was invested in making the Duramax warm up adequately in cold weather. This is one reason why they included a winter front package. The LB7's water-cooled turbocharger was another strategy used for quicker warmups. Engine coolant is routed through the LB7 turbo center section till the engine reaches operating temperature, then a thermostat blocks coolant flow.

Congrats on the new truck! smile.gif

MP

[david]

Thanks everyone and Merry Christmas to all!!!!!!
David :D