optimum operating temp

[Bentt]

what is the optimum opertaing temp for the 6.5 and what are the concerns with low operating temps

[Chevylover]

What do you mean with operating temp ?

Outside temp, cooling fluid temp, motor oil temp ???

Please explain more specific.

Cu,
Sven

[DieselFreak]

Guessing you don't mean outside temp, since you've got an intercooler - although it is ATA. IATs I cant remember.

Coolant temperatur shouldn't be lower than 180 F. Lower will trigger the ECM to enter "warm up"-mode.
If you are having problems staying around 180-210 F, you could consider a fan upgrade. Since your truck is a '97, it should already be fitted with the dual thermostat housing.

Max exhaust temperature is 1250 F.

Tranny and/or engine oil temps I cant remember either. Maybe you can, Sven :cool:

Bentt, have you tried searching the forum ?

[hraney]

I will assume you are talking about coolant temp. Seems GM wants the engine to run about 200 degrees F on coolant temp. Seems I read somewhere a long time ago about diesel not burning good until about 175F, below that and a diesel could start to "slobber". Unburnt fuel washes down the cylinder wall, contaminates the oil, makes a lot of wet soot in the exhaust and turbo. Oil flow could be an issue w/ REALLY low temps.
I don't know the specs are on the tranny temp, but I would assume around 200F since a lot of auto tranny coolers are run through the radiator. No idea about manual tranny or final drive temps.