C12 low oil pressure

bearings...... rods / mains

 

Probably have a bearing or bushing going out somewhere. Get an oil analysis done. Verify your readings with a mechanical gauge too to rule out a bad sensor.

 

Does this motor have the oil squirters that fall off?

 

Did it just start or has it been like that since you got the truck? Is that the pressure from the ECM or a mechanical gauge? Are you using the correct grade of oil?

 

Check gauge accuracy first, if thats all good then it sounds like they may have left one of the bolts out that holds the cam followers down, the cam followers are in two sets, the rear set has one extra hold down bolt at the very back, the exta bolts purpose is to block off the oil gallery at the rear cam journal, with out it you will get low oil pressure but not low enough to log a fault code.
There are many other possibilities but I've seen this several times before and its easy to check.

 

I have a c12 in my T600 and by what I've seen on other c12's and what I've been told, these engines have low oil pressure compared to
Other engines. But 10 at idle is way to low. My c12 has 600k miles and it's got minimum 20psi at idle and 40-42 running at 180 deg's at anything over 1,300 rpm's ..

 

i just noticed on my C12 the other day that my oil pressure at idle is down to about 16-17psi. normaly it would be at least 20-25 at idle depending on the oil temp. i have about 25000 miles on the motor since my inframe. I did switch over to full synthetic oil (Rotella T6) so not sure if that makes a difference?

any feedback would be greatly appreciated!

nick

 

Could be loose bearings, but it could be the oil pressure relief valve partially stuck open. Also, C12's have an external oil pump. Is there any signs of seepage around the back of the pump? If the O-rings start leaking, it could suck air.