Cm870 oil running hot

[Running rough]

Been noticing lately, oil will climb to 250 degrees Fahrenheit with out hardly worked engine, oil seems to heat up faster and takes longer to cool down, water temps are normal and don't climb to fast, anyone run into this issue and what is the most likely culprit, oil cooler?? I would like to get it fixed before I get a bad driver behind the wheel who doesn't moniter gauges and I will be faced with a wrecked engine and a big bill

[Signature620]

Probably your oil thermostat. It's behind the big plug at the very front of the oil cooler housing (you'll need a 19mm hex bit). You need to remove the A/C compresor, disconnect alternator (or let it hang if cables permit) then remove the bracket they mount to for access. Then you need a good pair of circlip pliers and a mirror to get the circlip and thermostat out. Just slip in the new one and reassemble. The roung side of the circlip goes to the front & the tension for the big plug is 74ft-lb (change the o-ring while you're at it.)

EDIT: Are you getting high oil temp faults? Also make sure your dash gauge and Cummins oil temp sensor are reading similar! Hate to do all that work for a bad gauge or sender, hahah.

[HankAz]

I did just what signature said and it fixed it. The hard part for mine was the snap ring pliers need to be long and narrow to get back in there though.
Good luck
Hank