Low Oil Pressure

[durallymax]

Searching doesn't do much as it just leads you to injector threads.

The crankcase was not overfull and did not smell of diesel at all. Blowby seemed kinda high. I could actually smell it when unhooking the plow, no hint of fuel in it though.

Lately the oil pressure was getting lower and lower like when injectors fail. Warning started coming on. So i just changed it now. On first start it went to 70. Well see what happens over the next few days.

Should I be suspecting the oil pressure switch next?

 

[BlkMax]

Without starting the oil battle......

What worked for low oil pressure at idle and operating temps was to change to Rotella T full synthetic. I got rid of the dino oil and used the synthetic. I'm sure any synthetic would have been better than the dino penzoil the dealer was putting in. At the time I had the "free" oil change deal....I never set off the light, but it was REALLY close.

I also do not have an auxiliary oil cooler in either truck. Keep in mind I live in Alaska, and my ambient temps are typically lower that what other see.... summer or winter.

 

[delong_1]

why not take 5 min and put a mech. gauge on it and know what the pressure actually is?

 

[baggedLB7]

I think the steper motor is going out on mine . The other day I looked up and it was on zero just parked but my insight was reading 22 psi but when I started it up the next time the gauge was fine. But it has been reading funny here and there since.
But I have not had a warning come up for mine though.

 

[WVRigrat05]

Mine would go to zero too, I got scared at first but the motor sounded the same so I hammered down, got home and did a flush and went to synthetic oil, oil psi was good to go til the motor went last winter. I have an LB7 bottom end now and noticed the sending unit or oil pump shows/has a little lower pressure than the LLY did

 

[TheBac]

why not take 5 min and put a mech. gauge on it and know what the pressure actually is?

Yep...have to do this first before anything else.

 

[durallymax]

Yep...have to do this first before anything else.

That would be the next step if nothing changes. Just curious what other issues people have seen.

I doubt we'd have issues with one duramax out of the entire fleet, if it was the oil. Could be wrong though.

 

[motoking_1990]

^^^^ what's with the sig bahahaha forgot performance fuel pin

 

[durallymax]

Well the truck has pressure, two sending units have been tried and I replaced the ECM.

The truck now has issues communicating with the FICM and died the other day. Massaged the harness and it runs now. I'm dreading this.

I'll be cleaning the block grounds and inspecting the harness closer but I didn't see any immediate obvious issues.

Should I just replace the wiring harness with the extra one I have? Almost tempted to get it reading oil pressure and sell it. 200k on it and its tired. Our 2002 is dying too, lots of issues here and there and I think its just tired too. The LML is nearly at 90k with no issues and they are offering killer deals on new ones right now so I think we are going to go buy another LML and buy some cheap used half tons for running around because they are cheaper to fix.

 

[blk smoke lb7]

Mine was low after the rebuild I switched to 20w 50 syn and run it like I stole it.Its still a little low but thats how it is.I installed a new lbz oil pump tried the manual gauge its just on the lower side and thats the way it is for mine.

 

[durallymax]

This one reads 0. We smashed the dinger for the time being.

 

[Dallas S]

My lmm read low one day. Message and ding would pop up for split second at a time. Later that day the crank snapped.