Engine Oil Temperature

[TractorHauler]

What would be a normal operating range for engine oil temperature. I went and looked at a truck yesterday that was running 220-225 after a rather long test drive. The coolant temp was 185-190. What do you think? It had a Cummins ISX in it, PRE EGR.

[Orangetxguy]

What would be a normal operating range for engine oil temperature. I went and looked at a truck yesterday that was running 220-225 after a rather long test drive. The coolant temp was 185-190. What do you think? It had a Cummins ISX in it, PRE EGR.

Me thinks there are "issues" with that motor!

The oil should not be all that hot on a test drive, unless of course you were in the back woods of the Ozarks, on a windy wooded trail....pulling a 40,000 pound load.


Of course...it could just be a bad sensor...but which one??

[TractorHauler]

That is what I was thinking. I did not buy the truck because of this. Isn't there a thermostat in the oil cooler as well that could possibly be bad?

[Orangetxguy]

That is what I was thinking. I did not buy the truck because of this. Isn't there a thermostat in the oil cooler as well that could possibly be bad?

Ya know...I'm not mechanic enought to know if there is or not...but considering the size of the lines, the size of the cooler itself, and the fact that the coolant thermostat and fan selinoid control most of that...I really don't think there is one.


No worries....a true mechanic will be along!

[COLT]

I had the same issues with an 07 565, pulling my regular 140,000 lbs in the foothills the truck would derate on long hills when it got to 250 degrees.

The thermostat got changed/fixed but it would still do it on occasion, must be an issue with these engines.