Freebee

I think that is a previous repair... we can only see one side of it , need to see both sides to offer any advice/comment

is it this one https://www.scribd.com/document/461751869/Parts-Catalog-Cummins-QSB6-7-CPL426

over filling will show up on the dipstick won't it.....as soon as you pour it in the rocker cover it runs down into the sump even on the...

Oil inevitably ends up in the rocker cover as it escapes from the parts under the cover that are being lubricated, as such you cannot...

i would not use any detergent because if any detergent traces cross over to diesel it will disarm all of your filtration preventing it...