MXS C-15 Oil Pressure and Temperture

My NXS is 35 psi at idle and 62 psi at 1400 rpm... 980,000 miles on it.

I'd pop the pan off and check the bearings.

 

Yes it is true . The computer uses water temp and load % to determine oil temp.

There is no actual oil temp sensor .

 

the acert I had did. it should be in the bottom rear corner driverside of oil pan,

 

You are correct on the temperature being calculated, just like swaan stated.
I had a mxs a couple years ago that would derate due to low oil pressure. After it got hot while driving if you let of the throttle and then back on. The sensor would not register the pressure coming back up. Like going through the gears etc. It would only do it maybe 3 or 4 times a day. That took awhile to figure out.

 

If your truck had a oil temp sensor in the pan then that would be a kenworth installed item.
Kenworth installed them on drivers side on back of sump . On the caterpillar side they had no oil temp sensor . It gets calculated by the ecm by water temp and load factor then it gets sent to the data link to talk to the dash.

My westernstar has a oil temp Guage but there is no sensor on the engine. It gets it reading from the ecm that calculates it .

 

I run a 2006 KW w/c15 cat 550hp. At startup she pushes 70 psi normal run down the road 60psi idle 700 rpm 20 psi.

 

try a oil pressure sensor, they can cause this easy to change

 

05 international 9900 bxs 550
07 freightliner classic mxs 550
And my father's 07 Western Star mxs 550 all have the oil temp sensor in the pan rear driver side. Factory installed