Mystik 15w50 or Rotella T4 15w40 with Schaeffers 132?

[Redland1]

Motor is a 2004 Cummins ISX15.Wanting to increase oil pressure a little bit.Which would be the better choice?
Oil changes would $246 with Rotella and $270 with Mystik.

 

[JavierH19]

What is your oil pressure and what was it before. More importantly what is your consumption.

 

[JHZR2]

We need numbers. Is the issue stifle or operating? Are oil temps ok?

 

[ripcord]

Also, the gauge on the dash may not be accurate as it uses an electrical sensor that can go bad.

 

[Redland1]

We need numbers. Is the issue stifle or operating? Are oil temps ok?

18-20 psi at idle,33-35psi going down the road.200-230F.

 

[wpod]

Is the engine getting tired [mileage ] What is the pressure supposed to be? That is a pricy engine I would contact Cummins.

 

[ripcord]

Everything I could find online indicates that the ISX has an ECM controlled low pressure, high volume oil pump. 20 psi at hot idle is normal for these and so is 35 while cruising.

 

[kschachn]

Everything I could find online indicates that the ISX has an ECM controlled low pressure, high volume oil pump. 20 psi at hot idle is normal for these and so is 35 while cruising.

So if true then the grade isn’t going to make any difference in terms of pressure?

 

[ripcord]

So if true then the grade isn’t going to make any difference in terms of pressure?

Only if the bearings are so loose that the oil pump can't keep up and is at maximum output all the time.

 

[Redland1]

Between the two which is the better oil overall?

 

[Redland1]

700k miles on motor

 

[twX]

Between the two which is the better oil overall?

The Mystik only has a CI-4 plus certification, whereas the Rotella is CK-4. API CI-4 would have been the current standard when your engine was produced, so it will be fine, but CK-4 is a more stringent standard. I'd use the Rotella.

 

[facility1]

Mystik 15w-40 is a CK-4 plus,,&Cl-4, CK-4 ,semi synthetic,,,good oil for the price,,good reputation