What Davekc sd, probably needs a heui pump. My experience with CAT C-9, similar engine, 2006 motor went 1.3 million before major oil usage a problem, went thru about 4 heui's and pieced mealed the injectors as I went along except for once did full replacement. Most pumps didn't throw much debri but even a minute amount will cause problems. Run Howes and do not over dilute, run a gallon Howes /320 gallons fuel unless using to anti gel, makes for a smoother CAT, but that is the fuel side of the pump, so I don't believe it will help save the heui from grenading it's tiny roller bearings on the oil side.
Parts are too expensive. Didn't ever use my CAT warranties at a CAT dealer because Freightliner dealers could get me right in and they will honor CAT warranties for the most part. Freightliner in Mt Vernon, IL is the only one that wanted me to pay for $5,500 repair (heui and injectors) up front and reimburse me weeks later after CAT reimbursed them, which I ended up not doing after contacting CAT and talking to supervisors at the dealer to explain this is not how warranties works. The service writer was a real ringer let me tell you after some other issues I had on non warranty wheel bearing work.
The heui pump and price of injectors are my main gripes but have made good money and not too hard to do the labor myself. I do have to go to someone with the CAT ET to set the trim on the injectors.
So far, 200,000 on CAT certified reman and warranty has paid for one heui and 7 injectors. Since a old timer told me to run Howes, truck runs smoother and fuel mileage went from 9.2 to 9.7, allison 6 speed. Because the Howes runs thru the fuel, I don't think it will help the heui pump roller bearing failures on the oil side.
Sounds pretty cheap to me but if not running I'd be hesitant, I just don't like buying something you have to go right to work on, could turn into a major wasp nest.