Engine oil filter plugging in a Cummins ISX-15L

I have an ISX15 2350 engine in my Peterbilt. It burns about a gallon of oil per 2000miles. It's done it for awhile...but runs good.
Anyway, I had the bright idea to change oil this summer and filled it with Rotella 15w40 and a gallon of Lucas. Seemed to help a little but still had to add oil every few days. About a month or so later, I added another gallon of Lucas.
It didn't help much and continued adding 15w40 as necessary.
Then awhile later we did a full change using Valvoline conventional 15w40.
It ran about 6000 miles and the pressure was getting lower. I changed the filter and it was good again.
About 4000 miles later and it needed to be changed again.
Not sure what's going on.
Should I flush the engine and do oil change? Not sure if there's sludge or what ....

As far as filters, Cummins = Fleetguard. Personally, I would use nothing but Fleetguard on this truck. Looks like you need to use some Restore or HPL equivalent to see if you can clean this bad boy up. I would try that prior to an in-frame. A few gallons of liquid fix is cheaper than the rebuild. I agree with @OVERKILL stop using the Lucas oil additive. IMO, they make a somewhat decent fuel injector cleaner but their engine oil additive is not worth using. If you try the restore and it doesn't work you might want to try some 15w50 to see if that helps with consumption. Good luck with this situation.

Just my $0.02
 
I’m confused here, are or were the filters actually plugged or not?
The pressure was dropping. I was at about 31-32 psi at highway speed...oil temp was 215. Idle was dipping under 20.
Put in new filter and was back up to 38 at highway and 22 at idle. So I assume the filter was the issue.
 
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As far as filters, Cummins = Fleetguard. Personally, I would use nothing but Fleetguard on this truck. Looks like you need to use some Restore or HPL equivalent to see if you can clean this bad boy up. I would try that prior to an in-frame. A few gallons of liquid fix is cheaper than the rebuild. I agree with @OVERKILL stop using the Lucas oil additive. IMO, they make a somewhat decent fuel injector cleaner but their engine oil additive is not worth using. If you try the restore and it doesn't work you might want to try some 15w50 to see if that helps with consumption. Good luck with this situation.

Just my $0.02
As far as a HPL equivalent....would running Amsoil 15w40 signature diesel oil be worth trying to clean the engine. It's coming on winter here in Saskatchewan so I don't want to get into anything too thick.
I called an actual Cummins shop here about Restore awhile ago and they didn't even know what I was talking about.
 
As far as a HPL equivalent....would running Amsoil 15w40 signature diesel oil be worth trying to clean the engine. It's coming on winter here in Saskatchewan so I don't want to get into anything too thick.
I called an actual Cummins shop here about Restore awhile ago and they didn't even know what I was talking about.

An equivalent to PBR would have a much higher dose of esters than your typical HDEO, Dave @High Performance Lubricants would have to cook something up for you that fits the bill, no OTS 15W-40 is going to be blended in that manner.

Also, he could do a 10W-30 or 10W-40 or 5W-40 depending on what you wanted (even a 0W-40) if you are concerned about cold temperature performance.
 
In all seriousness, If the filters are plugging that quickly, you need to find the source of contamination.

A gallon every 2000 miles is a fair amount. If you have “chugging” blow by as opposed to a steady, smooth “stream” out the oil fill, there is very likely a ring sealing issue/liner wear with one or more cylinders.

Have you changed the CCV filter recently? How often does it plug up?

As previously stated, ditch the Lucas.
 
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In all seriousness, If the filters are plugging that quickly, you need to find the source of contamination.

A gallon every 2000 miles is a fair amount. If you have “chugging” blow by as opposed to a steady, smooth “stream” out the oil fill, there is very likely a ring sealing issue/liner wear with one or more cylinders.

Have you changed the CCV filter recently? How often does it plug up?

As previously stated, ditch the Lucas.
Has the maintenance free CCV filter installed. Did take the cover off a few weeks ago and is clean inside.
Yeah I tried the Lucas and have not put it back in after the oil change.
 
In all seriousness, If the filters are plugging that quickly, you need to find the source of contamination.

A gallon every 2000 miles is a fair amount. If you have “chugging” blow by as opposed to a steady, smooth “stream” out the oil fill, there is very likely a ring sealing issue/liner wear with one or more cylinders.

Have you changed the CCV filter recently? How often does it plug up?

As previously stated, ditch the Lucas.
I'm going to put a fleetguard filter in if it starts plugging again. Just to see if there's a difference
 
Oil consumption would have to be rings/liners. That is one issue...

Oil filter plugging up is a serious issue, I'd be very curious as to what is plugging them up. If a FG filter doesn't plug up then I'd not worry about it.

Not overly difficult to do a blow down test and record each cylinder. See if you have even wear or a problem just in one hole.
 
I have an ISX15 2350 engine in my Peterbilt. It burns about a gallon of oil per 2000miles. It's done it for awhile...but runs good.
Anyway, I had the bright idea to change oil this summer and filled it with Rotella 15w40 and a gallon of Lucas. Seemed to help a little but still had to add oil every few days. About a month or so later, I added another gallon of Lucas.
It didn't help much and continued adding 15w40 as necessary.
Then awhile later we did a full change using Valvoline conventional 15w40.
It ran about 6000 miles and the pressure was getting lower. I changed the filter and it was good again.
About 4000 miles later and it needed to be changed again.
Not sure what's going on.
Should I flush the engine and do oil change? Not sure if there's sludge or what ....
back in the day 500 miles to the quart wasn't considered bad. guy I worked for had a old NTC Cummins that went thru 3 gallons of oil a day and it didn't leak or smoke..
 
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