Truck Repair: excessive oil blowby

Question
Hello my friend thanks ahead of time for your work.. I own a 99 frht classic with the N14 select motor, red top I believe you would call it. 525 hp..We have around 640k on it now and it has been blowing oil around quite a bit. But after the turbo froze up and was replaced we are finding more blowby. We made a make shift catch can and notice it filling up faster now, and my son said he is having to add more oil than usual maby a gallon in 18 days he said. That may not be perfectly accurate. I saw in a previous post that the heads could need work, but it sounds like rings.. What do you think. We will do an oil sample right away also to see if there is anything obvious truck seems like it makes great power. Thanks, Art

Answer
A gallon in 18 days isn't too bad. Defininetly would do oil samples to check for wearable metals. Might take you 3 or 4 times sampling to get a idea whats normal for your truck and whats abnormal.  I would say your right on the rings. If you had a blown head gasket or something you would know she wouldn't run right. If you decide to tackle the project of the rings i would do a whole in frame liners and all. You could reuse your heads but in my experience reman heads are pretty cheap for the n-14 and most problems with that engine is it likes to drop valves. Roll your mains while your down there too.